CSS Transforms Module Level 1
CSS Transforms Module Level 1
Editor’s Draft
30 November 2025
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Editors:
L. David Baron
Google
Simon Fraser
Apple Inc
Dean Jackson
Apple Inc
Theresa O'Connor
Apple Inc
Dirk Schulze
Adobe Inc
Former Editors:
David Hyatt
Apple Inc
Chris Marrin
Apple Inc
Aryeh Gregor
Mozilla
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rules apply.
Abstract
CSS transforms allows elements styled with CSS to be transformed in two-dimensional space. This specification is the convergence of the
CSS 2D Transforms
and
SVG transforms
specifications.
CSS
is a language for describing the rendering of structured documents
(such as HTML and XML)
on screen, on paper, etc.
Status of this document
This is a public copy of the editors’ draft.
It is provided for discussion only and may change at any moment.
Its publication here does not imply endorsement of its contents by W3C.
Don’t cite this document other than as work in progress.
Please send feedback
by
filing issues in GitHub
(preferred),
including the spec code “css-transforms” in the title, like this:
“[css-transforms]
…summary of comment…
”.
All issues and comments are
archived
Alternately, feedback can be sent to the (
archived
) public mailing list
www-style@w3.org
This document is governed by the
18 August 2025 W3C Process Document
1.
Introduction
This section is not normative.
The CSS
visual formatting model
describes a coordinate system within each element is positioned. Positions and sizes in this coordinate space can be thought of as being expressed in pixels, starting in the origin of point with positive values proceeding to the right and down.
This coordinate space can be modified with the
transform
property. Using transform, elements can be translated, rotated and scaled.
1.1.
Module Interactions
This module defines a set of CSS properties that affect the visual rendering of elements to which those properties are applied; these effects are applied after elements have been sized and positioned according to the
visual formatting model
from
[CSS2]
. Some values of these properties result in the creation of a
containing block
, and/or the creation of a
stacking context
Transforms affect the rendering of backgrounds on elements with a value of
fixed
for the
background-attachment
property, which is specified in
[CSS3BG]
Transforms affect the client rectangles returned by the Element Interface Extensions
getClientRects()
and
getBoundingClientRect()
, which are specified in
[CSSOM-VIEW]
Transforms affect the computation of the
scrollable overflow region
as described by
[CSS-OVERFLOW-3]
1.2.
CSS Values
This specification follows the
CSS property definition conventions
from
[CSS2]
using the
value definition syntax
from
[CSS-VALUES-3]
Value types not defined in this specification are defined in CSS Values & Units
[CSS-VALUES-3]
Combination with other CSS modules may expand the definitions of these value types.
In addition to the property-specific values listed in their definitions,
all properties defined in this specification
also accept the
CSS-wide keywords
as their property value.
For readability they have not been repeated explicitly.
Terminology {#terminology}
==========================
When used in this specification, terms have the meanings assigned in this section.
transformable element
A transformable element is an element in one of these categories:
all elements whose layout is governed by the CSS box model except for non-replaced inline boxes, table-column boxes, and table-column-group boxes
[CSS2]
all SVG
paint server elements
, the
clipPath
element and SVG
renderable elements
with the exception of any descendant element of
text content elements
[SVG2]
transformed element
An element with a computed value other than
none
for the
transform
property.
user coordinate system
local coordinate system
In general, a coordinate system defines locations and distances on the current canvas. The current local coordinate system (also user coordinate system) is the coordinate system that is currently active and which is used to define how coordinates and lengths are located and computed, respectively, on the current canvas.
The current user coordinate system has its origin at the top-left of a
reference box
specified by the
transform-box
property. Percentage values are relative to the dimension of this reference box. One unit equals one CSS pixel.
transformation matrix
A matrix that defines the mathematical mapping from one coordinate system into another. It is computed from the values of the
transform
and
transform-origin
properties as described
below
current transformation matrix
(CTM)
A matrix that defines the mapping from the
local coordinate system
into the
viewport coordinate system
2D matrix
A 3x2 transformation matrix, or a 4x4 matrix where the items m
31
, m
32
, m
13
, m
23
, m
43
, m
14
, m
24
, m
34
are equal to
and m
33
, m
44
are equal to
identity transform function
transform function
that is equivalent to a identity 4x4 matrix (see
Mathematical Description of Transform Functions
). Examples for identity transform functions are
translate(0)
translateX(0)
translateY(0)
scale(1)
scaleX(1)
scaleY(1)
rotate(0)
skew(0, 0)
skewX(0)
skewY(0)
and
matrix(1, 0, 0, 1, 0, 0)
post-multiply
post-multiplied
Term
post-multiplied by term
is equal to
pre-multiply
pre-multiplied
Term
pre-multiplied by term
is equal to
multiply
Multiply term
by term
is equal to
2.
The Transform Rendering Model
This section is normative.
Specifying a value other than
none
for the
transform
property establishes a new
local coordinate system
at the element that it is applied to. The mapping from where the element would have rendered into that local coordinate system is given by the element’s
transformation matrix
The
transformation matrix
is computed from the
transform
and
transform-origin
properties as follows:
Start with the identity matrix.
Translate by the computed X and Y of
transform-origin
Multiply by each of the transform functions in
transform
property from left to right
Translate by the negated computed X and Y values of
transform-origin
An element has a
transform
property that is not
none
div
transform-origin
transform
translate
-10
px
-20
px
scale
rotate
45
deg
);
The
transform-origin
property is set to
0 0
and can be omitted. The
transformation matrix
TM
gets computed by post-multiplying the
and
s.
Transforms apply to
transformable elements
The coordinate space is a coordinate system with two axes: the X axis increases horizontally to the right; the Y axis increases vertically downwards.
Transformations are cumulative. That is, elements establish their local coordinate system within the coordinate system of their parent.
To map a point
local
with the coordinate pair
local
and
local
from the
local coordinate system
of an element into the parent’s coordinate system, post-multiply the
transformation matrix
TM
of the element by
local
. The result is the mapped point
parent
with the coordinate pair
parent
and
parent
in the parent’s
local coordinate system
From the perspective of the user, an element effectively accumulates all the
transform
properties of its ancestors as well as any local transform applied to it. The accumulation of these transforms defines a
current transformation matrix
(CTM) for the element.
The
current transformation matrix
is computed by post-multiplying all transformation matrices starting from the
viewport coordinate system
and ending with the
transformation matrix
of an element.
This example has multiple, nested elements in an SVG document. Some elements get transformed by a
transformation matrix
svg
xmlns
"http://www.w3.org/2000/svg"
transform
"translate(-10, 20)"
transform
"scale(2)"
rect
width
"200"
height
"200"
transform
"rotate(45)"
/>
svg
translate(-10, 20)
computes to the transformation matrix
T1
scale(2)
computes to the transformation matrix
T2
rotate(45)
computes to the transformation matrix
T3
The CTM for the SVG
rect
element is the result of multiplying
T1
T2
and
T3
in order.
To map a point
local
with the coordinate pair
local
and
local
from the
local coordinate system
of the SVG
rect
element into the
viewport coordinate system
, post-multiply the
current transformation matrix
CTM
of the element by
local
. The result is the mapped point
viewport
with the coordinate pair
viewport
and
viewport
in the
viewport coordinate system
Note:
Transformations do affect the visual rendering, but have no effect on the CSS layout other than affecting overflow. Transforms are also taken into account when computing client rectangles exposed via the Element Interface Extensions, namely
getClientRects()
and
getBoundingClientRect()
, which are specified in
[CSSOM-VIEW]
div
transform
translate
100
px
100
px
);
This transform moves the element by 100 pixels in both the X and Y directions.
div
height
100
px
width
100
px
transform-origin
50
px
50
px
transform
rotate
45
deg
);
The
transform-origin
property moves the point of origin by 50 pixels in both the X and Y directions. The transform rotates the element clockwise by 45° about the point of origin. After all transform functions were applied, the translation of the origin gets translated back by -50 pixels in both the X and Y directions.
div
height
100
px
width
100
px
transform
translate
80
px
80
px
scale
1.5
1.5
rotate
45
deg
);
The visual appearance is as if the
div
element gets translated by 80px to the bottom left direction, then scaled up by 150% and finally rotated by 45°.
Each
can get represented by a corresponding 4x4 matrix. To map a point from the coordinate space of the
div
box to the coordinate space of the parent element, these transforms get multiplied in the reverse order:
The rotation matrix gets
post-multiplied
by the scale matrix.
The result of the previous multiplication is then
post-multiplied
by the translation matrix to create the accumulated transformation matrix.
Finally, the point to map gets
pre-multiplied
with the accumulated transformation matrix.
For more details see
The Transform Function Lists
Note:
The identical rendering can be obtained by nesting elements with the equivalent transforms:
div
style
"transform: translate(80px, 80px)"
div
style
"transform: scale(1.5, 1.5)"
div
style
"transform: rotate(45deg)"
>div
div
div
For elements whose layout is governed by the CSS box model, the transform property does not affect the flow of the content surrounding the transformed element. However, the extent of the overflow area takes into account transformed elements. This behavior is similar to what happens when elements are offset via relative positioning. Therefore, if the value of the
overflow
property is
scroll
or
auto
, scrollbars will appear as needed to see content that is transformed outside the visible area. Specifically, transforms can extend (but do not shrink) the size of the overflow area, which is computed as the union of the bounds of the elements before and after the application of transforms.
For elements whose layout is governed by the CSS box model, any value other than
none
for the
transform
property results in the creation of a stacking context. Implementations must paint the layer it creates, within its parent stacking context, at the same stacking order that would be used if it were a positioned element with
z-index: 0
. If an element with a transform is positioned, the
z-index
property applies as described in
[CSS2]
, except that
auto
is treated as
since a new stacking context is always created.
For elements whose layout is governed by the CSS box model, any value other than
none
for the
transform
property also causes the element to establish a
containing block for all descendants
. Its padding box will be used to layout for all of its absolute-position descendants, fixed-position descendants, and descendant fixed background attachments.
To demonstrate the effect of
containing block for all descendants
on fixed-position descendants, the following code snippets should behave identically:
style
container
width
300
px
height
200
px
border
px
dashed
black
padding
px
overflow
scroll
bloat
height
1000
px
child
right
bottom
width
10
height
10
background
green
style
div
id
"container"
style
"transform:translateX(5px);"
div
id
"bloat"
>div
div
id
"child"
style
"position:fixed;"
>div
div
versus
div
id
"container"
style
"position:relative; z-index:0; left:5px;"
div
id
"bloat"
>div
div
id
"child"
style
"position:absolute;"
>div
div
When the background of an element is propagated to the canvas
(see
CSS Backgrounds 3
§ 2.11.1 The Canvas Background and the Root Element
and
CSS Backgrounds 3
§ 2.11.2 The Canvas Background and the HTML Element
),
that background is not affected by any transform specified for that element or for the root element.
For elements that are effected by a transform
(i.e. have a transform applied to them, or to any of their ancestor elements)
and do not have their background propagated to the canvas,
a value of
fixed
for the
background-attachment
property
is treated as if it had a value of
scroll
The computed value of
background-attachment
is not affected.
3.
The
transform
Property
A transformation is applied to the coordinate system an element renders into through the
transform
property. This property contains a list of
transform functions
. The final transformation value for a coordinate system is obtained by converting each function in the list to its corresponding matrix like defined in
Mathematical Description of Transform Functions
, then multiplying the matrices.
Name:
transform
Value:
none
Initial:
none
Applies to:
transformable elements
Inherited:
no
Percentages:
refer to the size of
reference box
Computed value:
as specified, but with lengths made absolute
Canonical order:
per grammar
Animation type:
transform list, see
interpolation rules
Any computed value other than
none
for the transform affects containing block and stacking context, as described in
§ 2 The Transform Rendering Model
3.1.
Serialization of
To serialize the
s, serialize as per their individual grammars, in the order the grammars are written in, avoiding
expressions where possible, avoiding
transformations, omitting components when possible without changing the meaning, joining space-separated tokens with a single space, and following each serialized comma with a single space.
3.2.
Resolved value of
transform
The
transform
property is a
resolved value special case property
[CSSOM]
When the
computed value
is a
the
resolved value
is one
function
computed by the following algorithm:
Let
transform
be a 4x4 matrix initialized to the identity matrix. The elements
m11
m22
m33
and
m44
of
transform
must be set to
; all other elements of
transform
must be set to
Post-multiply all
s in
to
transform
Serialize
transform
to a
function.
For other computed values, the
resolved value
is the
computed value
4.
The
transform-origin
Property
Name:
transform-origin
Value:
[ left
center
right
top
bottom
[ left
center
right
[ top
center
bottom
[ [ center
left
right ]
&&
[ center
top
bottom ] ]
Initial:
50% 50%
Applies to:
transformable elements
Inherited:
no
Percentages:
refer to the size of
reference box
Computed value:
see
background-position
Canonical order:
per grammar
Animation type:
by computed value
The values of the
transform
and
transform-origin
properties are used to compute the
transformation matrix
, as described above.
If only one value is specified, the second value is assumed to be
center
. If one or two values are specified, the third value is assumed to be
0px
If two or more values are defined and either no value is a keyword, or the only used keyword is
center
, then the first value represents the horizontal position (or offset) and the second represents the vertical position (or offset). A third value always represents the Z position (or offset) and must be of type
A percentage for the horizontal offset is relative to the width of the
reference box
. A percentage for the vertical offset is relative to the height of the
reference box
. The value for the horizontal and vertical offset represent an offset from the top left corner of the
reference box
A length value gives a fixed length as the offset. The value for the horizontal and vertical offset represent an offset from the top left corner of the
reference box
top
Computes to
0%
for the vertical position.
right
Computes to
100%
for the horizontal position.
bottom
Computes to
100%
for the vertical position.
left
Computes to
0%
for the horizontal position.
center
Computes to
50%
left 50%
) for the horizontal position if the horizontal position is not otherwise specified, or
50%
top 50%
) for the vertical position if it is.
For SVG elements without associated CSS layout box the initial
used value
is
0 0
as if the user agent style sheet contained:
*:not
svg
),
*:not
foreignObject
> svg
transform-origin
The
transform-origin
property is a
resolved value special case property
like
height
[CSSOM]
5.
Transform reference box: the
transform-box
property
Name:
transform-box
Value:
content-box
border-box
fill-box
stroke-box
view-box
Initial:
view-box
Applies to:
transformable elements
Inherited:
no
Percentages:
N/A
Computed value:
specified keyword
Canonical order:
per grammar
Animation type:
discrete
All transformations defined by the
transform
and
transform-origin
property are relative to the position and dimensions of the
reference box
of the element. The
reference box
is specified by one of the following:
content-box
Uses the content box as reference box. The reference box of a table is the border box of its
table wrapper box
, not its table box.
border-box
Uses the border box as reference box. The reference box of a table is the border box of its
table wrapper box
, not its table box.
fill-box
Uses the
object bounding box
as reference box.
stroke-box
Uses the
stroke bounding box
as reference box.
view-box
Uses the nearest
SVG viewport
as reference box.
If a
viewBox
attribute is specified for the
SVG viewport
creating element:
The reference box is positioned at the origin of the coordinate system established by the
viewBox
attribute.
The dimension of the reference box is set to the
width
and
height
values of the
viewBox
attribute.
For the SVG
pattern
element, the reference box gets defined by the
patternUnits
attribute
[SVG2]
For the SVG
linearGradient
and
radialGradient
elements, the reference box gets defined by the
gradientUnits
attribute
[SVG2]
For the SVG
clipPath
element, the reference box gets defined by the
clipPathUnits
attribute
[CSS-MASKING]
A reference box adds an additional offset to the origin specified by the
transform-origin
property.
For SVG elements without associated CSS layout box, the
used value
for
content-box
is
fill-box
and for
border-box
is
stroke-box
For elements with associated CSS layout box, the
used value
for
fill-box
is
content-box
and for
stroke-box
and
view-box
is
border-box
6.
The SVG
transform
Attribute
6.1.
SVG presentation attributes
The
transform-origin
CSS property is also a
presentation attribute
and extends the list of existing
presentation attributes
[SVG2]
SVG 2 defines the
transform
patternTransform
gradientTransform
attributes as
presentation attributes
, represented by the CSS
transform
property
[SVG2]
The participation in the CSS cascade is determined by the specificity of
presentation attributes
in the SVG specification. According to SVG, user agents conceptually insert a
new author style sheet
for presentation attributes, which is the first in the author style sheet collection
[SVG2]
This example shows the combination of the
transform
style property and the
transform
attribute.
"http://www.w3.org/2000/svg"
"container"
transform=
"translate(200 200)"
"100"
height=
"100"
fill=
"blue"
/>
Because of the participation to the CSS cascade, the
transform
style property overrides the
transform
attribute. Therefore the container gets translated by
100px
in both the horizontal and the vertical directions, instead of
200px
6.2.
Syntax of the SVG
transform
attribute
For backwards compatibility reasons, the syntax of the
transform
patternTransform
gradientTransform
attributes differ from the syntax of the
transform
CSS property. For the attributes, there is no support for additional
s defined for the CSS
transform
property. Specifically,
and
are not supported by the
transform
patternTransform
gradientTransform
attributes.
The following list uses the Backus-Naur Form (BNF) to define values for the
transform
patternTransform
and
gradientTransform
attributes followed by an informative rail road diagram. The following notation is used:
*: 0 or more
+: 1 or more
?: 0 or 1
(): grouping
|: separates alternatives
double quotes surround literals. Literals consists of
letter
[CSS-SYNTAX-3]
, left parenthesis and right parenthesis.
defined by the CSS Syntax module
[CSS-SYNTAX-3]
Note:
The syntax reflects implemented behavior in user agents and differs from the syntax defined by SVG 1.1.
left parenthesis (
U+0028 LEFT PARENTHESIS
right parenthesis )
U+0029 RIGHT PARENTHESIS
comma
U+002C COMMA.
wsp
Either a U+000A LINE FEED, U+000D CARRIAGE RETURN, U+0009 CHARACTER TABULATION, or U+0020 SPACE.
comma-wsp
(wsp+ comma? wsp*) | (comma wsp*)
translate
"translate" wsp* "(" wsp* number ( comma-wsp? number )? wsp* ")"
scale
"scale" wsp* "(" wsp* number ( comma-wsp? number )? wsp* ")"
rotate
"rotate" wsp* "(" wsp* number ( comma-wsp? number comma-wsp? number )? wsp* ")"
skewX
"skewX" wsp* "(" wsp* number wsp* ")"
skewY
"skewY" wsp* "(" wsp* number wsp* ")"
matrix
"matrix" wsp* "(" wsp*
number comma-wsp?
number comma-wsp?
number comma-wsp?
number comma-wsp?
number comma-wsp?
number wsp* ")"
transform
matrix
| translate
| scale
| rotate
| skewX
| skewY
transforms
transform
| transform comma-wsp? transforms
transform-list
wsp* transforms? wsp*
6.3.
SVG transform functions
SVG transform functions of the
transform
patternTransform
gradientTransform
attributes defined by the syntax above are mapped to CSS
s as follows:
SVG transform function
CSS
Additional notes
translate
Number values interpreted as CSS
types with
px
units.
scale
rotate
Only single value version. Number value interpreted as CSS
type with
deg
unit.
skewX
Number value interpreted as CSS
type with
deg
unit.
skewY
Number value interpreted as CSS
type with
deg
unit.
matrix
The SVG transform function
rotate
with 3 values can not be mapped to a corresponding CSS
. The 2 optional number values represent a horizontal translation value
cx
followed by a vertical translation value
cy
. Both number values get interpreted as CSS
types with
px
units and define the origin for rotation. The behavior is equivalent to an initial translation by
cx
cy
, a rotation defined by the first number value interpreted as
type with
deg
unit followed by a translation by
-cx
-cy
transform
attribute can be the start or end value of a CSS Transition. If the value of a
transform
attribute is the start or end value of a CSS Transition and the SVG
transform list
contains at least one
rotate
transform function with 3 values, the individual SVG transform functions must get
post-multiplied
and the resulting matrix must get mapped to a
CSS
and used as start/end value of the CSS Transition.
6.4.
User coordinate space
For the
pattern
element, the
patternTransform
attribute and
transform
property define an additional transformation in the pattern coordinate system. See
patternUnits
attribute for details
[SVG2]
For the
linearGradient
and
radialGradient
elements, the
gradientTransform
attribute and
transform
property define an additional transformation in the gradient coordinate system. See
gradientUnits
attribute for details
[SVG2]
For the
clipPath
element, the
transform
attribute and
transform
property define an additional transformation in the clipping path coordinate space. See
clipPathUnits
attribute for details
[CSS-MASKING]
For all other
transformable elements
the
transform
attribute and
transform
property define a transformation in the current user coordinate system of the parent. All percentage values of the
transform
attribute are relative to the element’s
reference box
The
transform-origin
property on the pattern in the following example specifies a
50%
translation of the origin in the horizontal and vertical dimension. The
transform
property specifies a translation as well, but in absolute lengths.
"http://www.w3.org/2000/svg"
"pattern-1"
"rect1"
width=
"100"
height=
"100"
fill=
"blue"
/>
"200"
height=
"200"
fill=
"url(#pattern-1)"
/>
An SVG
pattern
element doesn’t have a bounding box. The
reference box
of the referencing
rect
element is used instead to solve the relative values of the
transform-origin
property. Therefore the point of origin will get translated by 100 pixels temporarily to rotate the user space of the
pattern
elements content.
6.5.
SVG DOM interface for the
transform
attribute
The SVG specification defines the "
SVGAnimatedTransformList
" interface in the SVG DOM to provide access to the animated and the base value of the SVG
transform
gradientTransform
and
patternTransform
attributes. To ensure backwards compatibility, this API must still be supported by user agents.
baseVal
gives the author the possibility to access and modify the values of the SVG
transform
patternTransform
gradientTransform
attributes. To provide the necessary backwards compatibility to the SVG DOM,
baseVal
must reflect the values of this author style sheet. All modifications to SVG DOM objects of
baseVal
must affect this author style sheet immediately.
animVal
represents the computed style of the
transform
property. Therefore it includes all applied
CSS3 Transitions
CSS3 Animations
or SVG Animations if any of those are underway. The computed style and SVG DOM objects of
animVal
can not be modified.
7.
The Transform Functions
The value of the
transform
property is a list of
The set of allowed transform functions is given below.
In the following functions,
behaves the same as
0deg
("unitless 0" angles are preserved for legacy compat).
A percentage for horizontal translations is relative to the width of the
reference box
A percentage for vertical translations is relative to the height of the
reference box
7.1.
2D Transform Functions
matrix()
= matrix(
#{6}
specifies a 2D transformation in the form of a
transformation matrix
of the six values a, b, c, d, e, f.
translate()
= translate(
specifies a
2D translation
by the vector [tx, ty], where tx is the first translation-value parameter and ty is the optional second translation-value parameter. If
is not provided, ty has zero as a value.
translateX()
= translateX(
specifies a
translation
by the given amount in the X direction.
translateY()
= translateY(
specifies a
translation
by the given amount in the Y direction.
scale()
= scale(
specifies a
2D scale
operation by the [sx,sy] scaling vector described by the 2 parameters. If the second parameter is not provided, it takes a value equal to the first. For example, scale(1, 1) would leave an element unchanged, while scale(2, 2) would cause it to appear twice as long in both the X and Y axes, or four times its typical geometric size.
scaleX()
= scaleX(
specifies a
2D scale
operation using the [sx,1] scaling vector, where sx is given as the parameter.
scaleY()
= scaleY(
specifies a
2D scale
operation using the [1,sy] scaling vector, where sy is given as the parameter.
rotate()
= rotate( [
] )
specifies a
2D rotation
by the angle specified in the parameter about the origin of the element, as defined by the
transform-origin
property. For example,
rotate(90deg)
would cause elements to appear rotated one-quarter of a turn in the clockwise direction.
skew()
= skew( [
specifies a
2D skew
by [ax,ay] for X and Y. If the second parameter is not provided, it has a zero value.
skew()
exists for compatibility reasons, and should not be used in new content. Use
skewX()
or
skewY()
instead, noting that the behavior of
skew()
is different from multiplying
skewX()
with
skewY()
skewX()
= skewX( [
] )
specifies a
2D skew transformation along the X axis
by the given angle.
skewY()
= skewY( [
] )
specifies a
2D skew transformation along the Y axis
by the given angle.
7.2.
Transform function primitives and derivatives
Some transform functions can be represented by more generic transform functions. These transform functions are called derived transform functions, and the generic transform functions are called primitive transform functions. Two-dimensional primitives and their derived transform functions are:
translate()
for
and
scale()
for
and
8.
The Transform Function Lists
If a list of
s is provided, then the net effect is as if each transform function had been specified separately in the order provided.
That is, in the absence of other styling that affects position and dimensions, a nested set of transforms is equivalent to a single list of transform functions, applied from the coordinate system of the ancestor to the
local coordinate system
of a given element. The resulting transform is the matrix multiplication of the list of transforms.
For example,
div
style
"transform: translate(-10px, -20px) scale(2) rotate(45deg)"
/>
is functionally equivalent to:
div
style
"transform: translate(-10px, -20px)"
id
"root"
div
style
"transform: scale(2)"
div
style
"transform: rotate(45deg)"
div
div
div
If a transform function causes the
current transformation matrix
of an object to be non-invertible, the object and its content do not get displayed.
The object in the following example gets scaled by 0.
style
box
transform
scale
);
style
div
class
"box"
Not visible
div
The scaling causes a non-invertible CTM for the coordinate space of the div box. Therefore neither the div box, nor the text in it get displayed.
9.
Interpolation of Transforms
Interpolation
of transform function lists is performed as follows:
If both
and
are
none
result
is
none
Treating
none
as a list of zero length,
if
or
differ in length:
extend the shorter list to the length of the longer list,
setting the function at each additional position
to the
identity transform function
matching
the function at the corresponding position in the longer list.
Both transform function lists are then interpolated
following the next rule.
For example, if
is
scale(2)
and
is
none
then the value
scale(1)
will be used for
and interpolation will proceed using the next rule.
Similarly, if
is
scale(1)
and
is
scale(2) rotate(50deg)
then the interpolation will be performed as if
were
scale(1) rotate(0)
Let
result
be an empty list.
Beginning at the start of
and
compare the corresponding functions at each position:
While the functions have either the same name,
or are derivatives of the same
primitive transform function
interpolate the corresponding pair of functions as described in
§ 10 Interpolation of primitives and derived transform functions
and append the result to
result
If the pair do not have a common name
or
primitive transform function
post-multiply the remaining transform functions in each of
and
respectively
to produce two 4x4 matrices.
Interpolate
these two matrices as described in
§ 11 Interpolation of Matrices
append the result to
result
and cease iterating over
and
For example,
if
is
rotate(0deg) scale(1) translate(20px)
and
is
rotate(270deg) translate(10px) scale(2)
the
rotate(0deg)
and
rotate(360deg)
functions will be interpolated
according to
§ 10 Interpolation of primitives and derived transform functions
while the remainder of each list—
scale(1) translate(20px)
and
translate(10px) scale(2)
—will first be converted to equivalent 4x4 matrices
and then interpolated as described in
§ 11 Interpolation of Matrices
A previous version of this specification
did not attempt to interpolate matching pairs of transform functions
unless all functions in the list matched.
As a result, the two lists in this example would be interpolated
using matrix interpolation only
and the
rotate(360deg)
component of the second list would be lost.
In some cases, an animation might cause a transformation matrix to be singular or non-invertible. For example, an animation in which scale moves from 1 to -1. At the time when the matrix is in such a state, the transformed element is not rendered.
10.
Interpolation of primitives and derived transform functions
Two transform functions with the same name and the same number of arguments are interpolated numerically without a former conversion. The calculated value will be of the same transform function type with the same number of arguments. Special rules apply to
The two transform functions
translate(0)
and
translate(100px)
are of the same type, have the same number of arguments and therefore can get interpolated numerically.
translateX(100px)
is not of the same type and
translate(100px, 0)
does not have the same number of arguments, therefore these transform functions can not get interpolated without a former conversion step.
Two different types of transform functions that share the same primitive, or transform functions of the same type with different number of arguments can be interpolated. Both transform functions need a former conversion to the common primitive first and get interpolated numerically afterwards. The computed value will be the primitive with the resulting interpolated arguments.
The following example describes a transition from
translateX(100px)
to
translateY(100px)
in 3 seconds on hovering over the div box. Both transform functions derive from the same primitive
translate()
and therefore can be interpolated.
div
transform
translateX
100
px
);
div:hover
transform
translateY
100
px
);
transition
transform
For the time of the transition both transform functions get transformed to the common primitive.
translateX(100px)
gets converted to
translate(100px, 0)
and
translateY(100px)
gets converted to
translate(0, 100px)
. Both transform functions can then get interpolated numerically.
If both transform functions share a primitive in the two-dimensional space, both transform functions get converted to the two-dimensional primitive. If one or both transform functions are three-dimensional transform functions, the common three-dimensional primitive is used.
In this example a two-dimensional transform function gets animated to a three-dimensional transform function. The common primitive is
translate3d()
div
transform
translateX
100
px
);
div:hover
transform
translateZ
100
px
);
transition
transform
First
translateX(100px)
gets converted to
translate3d(100px, 0, 0)
and
translateZ(100px)
to
translate3d(0, 0, 100px)
respectively. Then both converted transform functions get interpolated numerically.
11.
Interpolation of Matrices
When interpolating between two matrices, each matrix is decomposed into the corresponding translation, rotation, scale, skew. Each corresponding component of the decomposed matrices gets interpolated numerically and recomposed back to a matrix in a final step.
In the following example the element gets translated by 100 pixel in both the X and Y directions and rotated by 1170° on hovering. The initial transformation is 45°. With the usage of transition, an author might expect a animated, clockwise rotation by three and a quarter turns (1170°).
style
div
transform
rotate
45
deg
);
div
hover
transform
translate
100
px
100
px
rotate
1215
deg
);
transition
transform
style
div
>div
The number of transform functions on the source transform
rotate(45deg)
differs from the number of transform functions on the destination transform
translate(100px, 100px) rotate(1125deg)
. According to the last rule of
Interpolation of Transforms
, both transforms must be interpolated by matrix interpolation. With converting the transformation functions to matrices, the information about the three turns gets lost and the element gets rotated by just a quarter turn (90°).
To achieve the three and a quarter turns for the example above, source and destination transforms must fulfill the third rule of
Interpolation of Transforms
. Source transform could look like
translate(0, 0) rotate(45deg)
for a linear interpolation of the transform functions.
In the following we differ between the
interpolation of two 2D matrices
and the interpolation of two matrices where at least one matrix is not a
2D matrix
If one of the matrices for interpolation is non-invertible, the used animation function must fall-back to a discrete animation according to the rules of the respective animation specification.
11.1.
Supporting functions
The pseudo code in the next subsections make use of the following supporting functions:
Supporting functions (point is a 3 component vector, matrix is a 4x4 matrix, vector is a 4 component vector):
double determinant(matrix) returns the 4x4 determinant of the matrix
matrix inverse(matrix) returns the inverse of the passed matrix
matrix transpose(matrix) returns the transpose of the passed matrix
point multVecMatrix(point, matrix) multiplies the passed point by the passed matrix
and returns the transformed point
double length(point) returns the length of the passed vector
point normalize(point) normalizes the length of the passed point to 1
double dot(point, point) returns the dot product of the passed points
double sqrt(double) returns the root square of passed value
double max(double y, double x) returns the bigger value of the two passed values
double dot(vector, vector) returns the dot product of the passed vectors
vector multVector(vector, vector) multiplies the passed vectors
double sqrt(double) returns the root square of passed value
double max(double y, double x) returns the bigger value of the two passed values
double min(double y, double x) returns the smaller value of the two passed values
double cos(double) returns the cosines of passed value
double sin(double) returns the sine of passed value
double acos(double) returns the inverse cosine of passed value
double abs(double) returns the absolute value of the passed value
double rad2deg(double) transforms a value in radian to degree and returns it
double deg2rad(double) transforms a value in degree to radian and returns it
Decomposition also makes use of the following function:
point combine(point a, point b, double ascl, double bscl)
result[0] = (ascl * a[0]) + (bscl * b[0])
result[1] = (ascl * a[1]) + (bscl * b[1])
result[2] = (ascl * a[2]) + (bscl * b[2])
return result
11.2.
Interpolation of 2D matrices
11.2.1.
Decomposing a 2D matrix
The pseudo code below is based upon the "unmatrix" method in "Graphics Gems II, edited by Jim Arvo".
Matrices in the pseudo code use the column-major order. The first index on a matrix entry represents the column and the second index represents the row.
Input: matrix ; a 4x4 matrix
Output: translation ; a 2 component vector
scale ; a 2 component vector
angle ; rotation
m11 ; 1,1 coordinate of 2x2 matrix
m12 ; 1,2 coordinate of 2x2 matrix
m21 ; 2,1 coordinate of 2x2 matrix
m22 ; 2,2 coordinate of 2x2 matrix
Returns false if the matrix cannot be decomposed, true if it can
double row0x = matrix[0][0]
double row0y = matrix[0][1]
double row1x = matrix[1][0]
double row1y = matrix[1][1]
translate[0] = matrix[3][0]
translate[1] = matrix[3][1]
scale[0] = sqrt(row0x * row0x + row0y * row0y)
scale[1] = sqrt(row1x * row1x + row1y * row1y)
// If determinant is negative, one axis was flipped.
double determinant = row0x * row1y - row0y * row1x
if (determinant < 0)
// Flip axis with minimum unit vector dot product.
if (row0x < row1y)
scale[0] = -scale[0]
else
scale[1] = -scale[1]
// Renormalize matrix to remove scale.
if (scale[0])
row0x *= 1 / scale[0]
row0y *= 1 / scale[0]
if (scale[1])
row1x *= 1 / scale[1]
row1y *= 1 / scale[1]
// Compute rotation and renormalize matrix.
angle = atan2(row0y, row0x);
if (angle)
// Rotate(-angle) = [cos(angle), sin(angle), -sin(angle), cos(angle)]
// = [row0x, -row0y, row0y, row0x]
// Thanks to the normalization above.
double sn = -row0y
double cs = row0x
double m11 = row0x
double m12 = row0y
double m21 = row1x
double m22 = row1y
row0x = cs * m11 + sn * m21
row0y = cs * m12 + sn * m22
row1x = -sn * m11 + cs * m21
row1y = -sn * m12 + cs * m22
m11 = row0x
m12 = row0y
m21 = row1x
m22 = row1y
// Convert into degrees because our rotation functions expect it.
angle = rad2deg(angle)
return true
11.2.2.
Interpolation of decomposed 2D matrix values
Before two decomposed 2D matrix values can be interpolated, the following
Input: translationA ; a 2 component vector
scaleA ; a 2 component vector
angleA ; rotation
m11A ; 1,1 coordinate of 2x2 matrix
m12A ; 1,2 coordinate of 2x2 matrix
m21A ; 2,1 coordinate of 2x2 matrix
m22A ; 2,2 coordinate of 2x2 matrix
translationB ; a 2 component vector
scaleB ; a 2 component vector
angleB ; rotation
m11B ; 1,1 coordinate of 2x2 matrix
m12B ; 1,2 coordinate of 2x2 matrix
m21B ; 2,1 coordinate of 2x2 matrix
m22B ; 2,2 coordinate of 2x2 matrix
// If x-axis of one is flipped, and y-axis of the other,
// convert to an unflipped rotation.
if ((scaleA[0] < 0 && scaleB[1] < 0) || (scaleA[1] < 0 && scaleB[0] < 0))
scaleA[0] = -scaleA[0]
scaleA[1] = -scaleA[1]
angleA += angleA < 0 ? 180 : -180
// Don't rotate the long way around.
if (!angleA)
angleA = 360
if (!angleB)
angleB = 360
if (abs(angleA - angleB) > 180)
if (angleA > angleB)
angleA -= 360
else
angleB -= 360
Afterwards, each component of the decomposed values translation, scale, angle, m11 to m22 of the source matrix get linearly interpolated with each corresponding component of the destination matrix.
11.2.3.
Recomposing to a 2D matrix
After interpolation, the resulting values are used to transform the elements user space. One way to use these values is to recompose them into a 4x4 matrix. This can be done following the pseudo code below.
Matrices in the pseudo code use the column-major order. The first index on a matrix entry represents the column and the second index represents the row.
Input: translation ; a 2 component vector
scale ; a 2 component vector
angle ; rotation
m11 ; 1,1 coordinate of 2x2 matrix
m12 ; 1,2 coordinate of 2x2 matrix
m21 ; 2,1 coordinate of 2x2 matrix
m22 ; 2,2 coordinate of 2x2 matrix
Output: matrix ; a 4x4 matrix initialized to identity matrix
matrix[0][0] = m11
matrix[0][1] = m12
matrix[1][0] = m21
matrix[1][1] = m22
// Translate matrix.
matrix[3][0] = translate[0] * m11 + translate[1] * m21
matrix[3][1] = translate[0] * m12 + translate[1] * m22
// Rotate matrix.
angle = deg2rad(angle);
double cosAngle = cos(angle);
double sinAngle = sin(angle);
// New temporary, identity initialized, 4x4 matrix rotateMatrix
rotateMatrix[0][0] = cosAngle
rotateMatrix[0][1] = sinAngle
rotateMatrix[1][0] = -sinAngle
rotateMatrix[1][1] = cosAngle
matrix = post-multiply(rotateMatrix, matrix)
// Scale matrix.
matrix[0][0] *= scale[0]
matrix[0][1] *= scale[0]
matrix[1][0] *= scale[1]
matrix[1][1] *= scale[1]
12.
Mathematical Description of Transform Functions
Mathematically, all transform functions can be represented as 4x4 transformation matrices of the following form:
One translation unit on a matrix is equivalent to 1 pixel in the local coordinate system of the element.
A 2D 3x2 matrix with six parameters
and
is equivalent to the matrix:
A 2D translation with the parameters
tx
and
ty
is equivalent to a 3D translation where
tz
has zero as a value.
A 2D scaling with the parameters
sx
and
sy
is equivalent to a 3D scale where
sz
has one as a value.
A 2D rotation with the parameter
alpha
is
equivalent to a 3D rotation with the vector [x,y,z] where
has zero as a value,
has zero as a value,
has one as a value, and the parameter
alpha
where:
A 2D skew like transformation with the parameters
alpha
and
beta
is equivalent to the matrix:
A 2D skew transformation along the X axis with the parameter
alpha
is equivalent to the matrix:
A 2D skew transformation along the Y axis with the parameter
beta
is equivalent to the matrix:
13.
Privacy Considerations
UAs must implement transform operations in a way attackers can not infer information and mount a timing attack.
A timing attack is a method of obtaining information about content that is otherwise protected, based on studying the amount of time it takes for an operation to occur.
At this point there are no information about potential privacy concerns specific to this specification.
14.
Security Considerations
At this point there are no information about potential security concerns specific to this specification.
Changes
Since the
14 February 2019 Candidate Recommendation
Relax syntax of
transform
attribute: Do not require commas between
items.
Simplified grammar of transform functions. (No normative impact.)
Remove animation support of
transform
from
animate
and
set
elements.
State that transforms do not transform backgrounds that are propagated to the canvas, and clarify some other interactions with background propagation.
Split privacy and security section.
Editorial changes.
Since the
30 November 2018 Working Draft
No substantive changes
Boilerplate, styling updates for CR
Since the
30 November 2017 Working Draft
Remove specification text that makes
patternTransform
gradientTransform
presentation attributes representing the
transform
property. That is going to get specified by SVG 2
[SVG2]
Added privacy and security section.
Use
[SVG2]
definitions for
transformable elements
Added special syntax for
transform
gradientTransform
and
patternTransform
attributes.
Clarify multiplication order by using terms
post-multiply
and
pre-multiply
Clarify index order of matrix entries in pseudo-code.
Clarify multiplication order in recomposition pseudo-code.
Clarify behavior of
transform
on overflow area.
Remove
translateX(0)
translateY(0)
scaleX(0)
scaleY(0)
from the list of neutral elements.
Remove any reference of 3D transformations of transform function definitions.
Specify interpolation between
s to match lengths and
avoid matrix interpolation for the common prefix of the two lists.
No
transform
on non-replaced inline boxes, table-column boxes, and table-column-group boxes.
Define target coordinate space for transformations on
pattern
linearGradient
radialGradient
and
clipPath
elements.
Remove 3-value
from transform function primitives.
Be more specific about computation of
transformation matrix
and
current transformation matrix
Define reference box for paint servers and
clipPath
element.
Specify behavior of transform presentation attribute with 3-value-rotate as start or end value of a transition.
Add
stroke-box
and
content-box
to
transform-box
. Align box mapping behavior across all specifications.
Editorial changes.
Acknowledgments
The editors would like to thank Robert O’Callahan, Cameron McCormack, Tab Atkins, Gérard Talbot, L. David Baron, Rik Cabanier, Brian Birtles, Benoit Jacob, Ken Shoemake, Alan Gresley, Maciej Stochowiak, Sylvain Galineau, Rafal Pietrak, Shane Stephens, Matt Rakow, XiangHongAi, Fabio M. Costa, Nivesh Rajbhandari, Rebecca Hauck, Gregg Tavares, Graham Clift, Erik Dahlström, Alexander Zolotov, Amelia Bellamy-Royds and Boris Zbarsky for their careful reviews, comments, and corrections.
Conformance
Document conventions
Conformance requirements are expressed with a combination of
descriptive assertions and RFC 2119 terminology. The key words “MUST”,
“MUST NOT”, “REQUIRED”, “SHALL”, “SHALL NOT”, “SHOULD”, “SHOULD NOT”,
“RECOMMENDED”, “MAY”, and “OPTIONAL” in the normative parts of this
document are to be interpreted as described in RFC 2119.
However, for readability, these words do not appear in all uppercase
letters in this specification.
All of the text of this specification is normative except sections
explicitly marked as non-normative, examples, and notes.
[RFC2119]
Examples in this specification are introduced with the words “for example”
or are set apart from the normative text with
class="example"
like this:
This is an example of an informative example.
Informative notes begin with the word “Note” and are set apart from the
normative text with
class="note"
, like this:
Note, this is an informative note.
Advisements are normative sections styled to evoke special attention and are
set apart from other normative text with
, like
this:
UAs MUST provide an accessible alternative.
Tests
Tests relating to the content of this specification
may be documented in “Tests” blocks like this one.
Any such block is non-normative.
Conformance classes
Conformance to this specification
is defined for three conformance classes:
style sheet
CSS
style sheet
renderer
UA
that interprets the semantics of a style sheet and renders
documents that use them.
authoring tool
UA
that writes a style sheet.
A style sheet is conformant to this specification
if all of its statements that use syntax defined in this module are valid
according to the generic CSS grammar and the individual grammars of each
feature defined in this module.
A renderer is conformant to this specification
if, in addition to interpreting the style sheet as defined by the
appropriate specifications, it supports all the features defined
by this specification by parsing them correctly
and rendering the document accordingly. However, the inability of a
UA to correctly render a document due to limitations of the device
does not make the UA non-conformant. (For example, a UA is not
required to render color on a monochrome monitor.)
An authoring tool is conformant to this specification
if it writes style sheets that are syntactically correct according to the
generic CSS grammar and the individual grammars of each feature in
this module, and meet all other conformance requirements of style sheets
as described in this module.
Partial implementations
So that authors can exploit the forward-compatible parsing rules to
assign fallback values, CSS renderers
must
treat as invalid (and
ignore
as appropriate
) any at-rules, properties, property values, keywords,
and other syntactic constructs for which they have no usable level of
support. In particular, user agents
must not
selectively
ignore unsupported component values and honor supported values in a single
multi-value property declaration: if any value is considered invalid
(as unsupported values must be), CSS requires that the entire declaration
be ignored.
Implementations of Unstable and Proprietary Features
To avoid clashes with future stable CSS features,
the CSSWG recommends
following best practices
for the implementation of
unstable
features and
proprietary extensions
to CSS.
Non-experimental implementations
Once a specification reaches the Candidate Recommendation stage,
non-experimental implementations are possible, and implementors should
release an unprefixed implementation of any CR-level feature they
can demonstrate to be correctly implemented according to spec.
To establish and maintain the interoperability of CSS across
implementations, the CSS Working Group requests that non-experimental
CSS renderers submit an implementation report (and, if necessary, the
testcases used for that implementation report) to the W3C before
releasing an unprefixed implementation of any CSS features. Testcases
submitted to W3C are subject to review and correction by the CSS
Working Group.
Further information on submitting testcases and implementation reports
can be found from on the CSS Working Group’s website at
Questions should be directed to the
public-css-testsuite@w3.org
mailing list.
Index
Terms defined by this specification
2D matrix
, in § 1.2
border-box
, in § 5
bottom
, in § 4
center
, in § 4
containing block for all descendants
, in § 2
content-box
, in § 5
current transformation matrix
, in § 1.2
fill-box
, in § 5
identity transform
, in § 1.2
identity transform function
, in § 1.2
left
, in § 4
local coordinate system
, in § 1.2
matrix()
, in § 7.1
multiply
, in § 1.2
post-multiplied
, in § 1.2
post-multiply
, in § 1.2
pre-multiplied
, in § 1.2
pre-multiply
, in § 1.2
reference box
, in § 5
right
, in § 4
rotate()
, in § 7.1
scale()
, in § 7.1
scaleX()
, in § 7.1
scaleY()
, in § 7.1
skew()
, in § 7.1
skewX()
, in § 7.1
skewY()
, in § 7.1
stroke-box
, in § 5
top
, in § 4
transform
, in § 3
transformable element
, in § 1.2
transformation matrix
, in § 1.2
transform-box
, in § 5
transformed element
, in § 1.2
, in § 7
, in § 3
transform-origin
, in § 4
translate()
, in § 7.1
translateX()
, in § 7.1
translateY()
, in § 7.1
user coordinate system
, in § 1.2
view-box
, in § 5
Terms defined by reference
[CSS-CASCADE-5]
defines the following terms:
computed value
used value
[CSS-MASKING]
defines the following terms:
clipPath
clipPathUnits
[CSS-OVERFLOW-3]
defines the following terms:
auto
overflow
scroll
[CSS-SIZING-3]
defines the following terms:
height
[CSS-SYNTAX-3]
defines the following terms:
letter
[CSS-TRANSFORMS-2]
defines the following terms:
translate3d()
[CSS-VALUES-4]
defines the following terms:
&&
calc()
CSS-wide keywords
deg
interpolate
interpolation
px
[CSS2]
defines the following terms:
auto
stacking context
z-index
[CSS3BG]
defines the following terms:
background-attachment
background-position
fixed
scroll
[CSSOM]
defines the following terms:
resolved value
resolved value special case property
[HTML]
defines the following terms:
div
[SVG-ANIMATIONS]
defines the following terms:
animate
set
[SVG1.1]
defines the following terms:
gradientTransform
gradientUnits
patternTransform
patternUnits
transform
[SVG2]
defines the following terms:
animVal
baseVal
linearGradient
object bounding box
paint server element
pattern
presentation attributes
radialGradient
rect
renderable element
stroke bounding box
text content element
viewBox
viewport coordinate system
References
Normative References
[CSS-CASCADE-5]
Elika Etemad; Miriam Suzanne; Tab Atkins Jr..
CSS Cascading and Inheritance Level 5
. URL:
[CSS-MASKING]
Dirk Schulze; Brian Birtles; Tab Atkins Jr..
CSS Masking Module Level 1
. URL:
[CSS-OVERFLOW-3]
Elika Etemad; Florian Rivoal.
CSS Overflow Module Level 3
. URL:
[CSS-SIZING-3]
Tab Atkins Jr.; Elika Etemad.
CSS Box Sizing Module Level 3
. URL:
[CSS-SYNTAX-3]
Tab Atkins Jr.; Simon Sapin.
CSS Syntax Module Level 3
. URL:
[CSS-VALUES-3]
Tab Atkins Jr.; Elika Etemad.
CSS Values and Units Module Level 3
. URL:
[CSS-VALUES-4]
Tab Atkins Jr.; Elika Etemad.
CSS Values and Units Module Level 4
. URL:
[CSS2]
Bert Bos; et al.
Cascading Style Sheets Level 2 Revision 1 (CSS 2.1) Specification
. URL:
[CSS3BG]
Elika Etemad; Brad Kemper.
CSS Backgrounds and Borders Module Level 3
. URL:
[CSSOM]
Daniel Glazman; Emilio Cobos Álvarez.
CSS Object Model (CSSOM)
. URL:
[RFC2119]
S. Bradner.
Key words for use in RFCs to Indicate Requirement Levels
. March 1997. Best Current Practice. URL:
[SVG-ANIMATIONS]
SVG Animations Level 2
. Editor's Draft. URL:
[SVG2]
Amelia Bellamy-Royds; et al.
Scalable Vector Graphics (SVG) 2
. URL:
Non-Normative References
[CSS-TRANSFORMS-2]
Tab Atkins Jr.; et al.
CSS Transforms Module Level 2
. URL:
[CSSOM-VIEW]
Simon Fraser; Emilio Cobos Álvarez.
CSSOM View Module
. URL:
[HTML]
Anne van Kesteren; et al.
HTML Standard
. Living Standard. URL:
Property Index
Name
Value
Initial
Applies to
Inh.
%ages
Animation type
Canonical order
Computed value
transform
none |
none
transformable elements
no
refer to the size of reference box
transform list, see interpolation rules
per grammar
as specified, but with lengths made absolute
transform-box
content-box | border-box | fill-box | stroke-box | view-box
view-box
transformable elements
no
N/A
discrete
per grammar
specified keyword
transform-origin
[ left | center | right | top | bottom |
50% 50%
transformable elements
no
refer to the size of reference box
by computed value
per grammar
see background-position
MDN
transform-box
In all current engines.
Firefox
55+
Safari
11+
Chrome
64+
Opera
Edge
79+
Edge (Legacy)
IE
None
Firefox for Android
iOS Safari
Chrome for Android
Android WebView
Samsung Internet
Opera Mobile
MDN
transform-origin
In all current engines.
Firefox
16+
Safari
9+
Chrome
36+
Opera
23+
Edge
79+
Edge (Legacy)
12+
IE
10+
Firefox for Android
iOS Safari
Chrome for Android
Android WebView
4.4+
Samsung Internet
Opera Mobile
24+
Attribute/transform-origin
Firefox
77+
Safari
None
Chrome
Yes
Opera
Edge
Yes
Edge (Legacy)
IE
Firefox for Android
None
iOS Safari
Chrome for Android
Android WebView
Samsung Internet
Opera Mobile
MDN
transform
In all current engines.
Firefox
16+
Safari
9+
Chrome
36+
Opera
23+
Edge
79+
Edge (Legacy)
12+
IE
10+
Firefox for Android
iOS Safari
9+
Chrome for Android
Android WebView
4.4+
Samsung Internet
Opera Mobile
24+
MDN
transform-function/matrix
In all current engines.
Firefox
3.5+
Safari
3.1+
Chrome
1+
Opera
10.5+
Edge
79+
Edge (Legacy)
12+
IE
9+
Firefox for Android
4+
iOS Safari
3.2+
Chrome for Android
Android WebView
2+
Samsung Internet
Opera Mobile
11+
MDN
transform-function/rotate
In all current engines.
Firefox
3.5+
Safari
3.1+
Chrome
1+
Opera
10.5+
Edge
79+
Edge (Legacy)
12+
IE
9+
Firefox for Android
iOS Safari
3.2+
Chrome for Android
Android WebView
2+
Samsung Internet
Opera Mobile
11+
MDN
transform-function/scale
In all current engines.
Firefox
3.5+
Safari
3.1+
Chrome
1+
Opera
10.5+
Edge
79+
Edge (Legacy)
12+
IE
9+
Firefox for Android
iOS Safari
3.2+
Chrome for Android
Android WebView
2+
Samsung Internet
Opera Mobile
11+
MDN
transform-function/scaleX
In all current engines.
Firefox
3.5+
Safari
3.1+
Chrome
1+
Opera
10.5+
Edge
79+
Edge (Legacy)
12+
IE
9+
Firefox for Android
iOS Safari
3.2+
Chrome for Android
Android WebView
2+
Samsung Internet
Opera Mobile
11+
MDN
transform-function/scaleY
In all current engines.
Firefox
3.5+
Safari
3.1+
Chrome
1+
Opera
10.5+
Edge
79+
Edge (Legacy)
12+
IE
9+
Firefox for Android
iOS Safari
3.2+
Chrome for Android
Android WebView
2+
Samsung Internet
Opera Mobile
11+
MDN
transform-function/skew
In all current engines.
Firefox
3.5+
Safari
3.1+
Chrome
1+
Opera
10.5+
Edge
79+
Edge (Legacy)
12+
IE
9+
Firefox for Android
4+
iOS Safari
3.2+
Chrome for Android
Android WebView
2+
Samsung Internet
Opera Mobile
11+
MDN
transform-function/skewX
In all current engines.
Firefox
3.5+
Safari
3.1+
Chrome
1+
Opera
10.5+
Edge
79+
Edge (Legacy)
12+
IE
9+
Firefox for Android
iOS Safari
3.2+
Chrome for Android
Android WebView
2+
Samsung Internet
Opera Mobile
11+
MDN
transform-function/skewY
In all current engines.
Firefox
3.5+
Safari
3.1+
Chrome
1+
Opera
10.5+
Edge
79+
Edge (Legacy)
12+
IE
9+
Firefox for Android
iOS Safari
3.2+
Chrome for Android
Android WebView
2+
Samsung Internet
Opera Mobile
11+
MDN
transform-function/translate
In all current engines.
Firefox
3.5+
Safari
3.1+
Chrome
1+
Opera
10.5+
Edge
79+
Edge (Legacy)
12+
IE
9+
Firefox for Android
iOS Safari
3.2+
Chrome for Android
Android WebView
2+
Samsung Internet
Opera Mobile
11+
MDN
transform-function/translateX
In all current engines.
Firefox
3.5+
Safari
3.1+
Chrome
1+
Opera
10.5+
Edge
79+
Edge (Legacy)
12+
IE
9+
Firefox for Android
iOS Safari
3.2+
Chrome for Android
Android WebView
2+
Samsung Internet
Opera Mobile
11+
MDN
transform-function/translateY
In all current engines.
Firefox
3.5+
Safari
3.1+
Chrome
1+
Opera
10.5+
Edge
79+
Edge (Legacy)
12+
IE
9+
Firefox for Android
iOS Safari
3.2+
Chrome for Android
Android WebView
2+
Samsung Internet
Opera Mobile
11+
MDN
transform-function
In all current engines.
Firefox
3.5+
Safari
3.1+
Chrome
1+
Opera
10.5+
Edge
79+
Edge (Legacy)
12+
IE
9+
Firefox for Android
iOS Safari
3.2+
Chrome for Android
Android WebView
2+
Samsung Internet
Opera Mobile
11+
MDN
Attribute/transform
In no current engines.
Firefox
Safari
Chrome
Opera
Edge
Edge (Legacy)
IE
Firefox for Android
iOS Safari
Chrome for Android
Android WebView
Samsung Internet
Opera Mobile
MDN
Attribute/gradientTransform
In all current engines.
Firefox
1.5+
Safari
3+
Chrome
1+
Opera
Edge
79+
Edge (Legacy)
IE
Firefox for Android
iOS Safari
Chrome for Android
Android WebView
Samsung Internet
Opera Mobile