width
Baseline Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
The width
CSS property sets an element's width. By default, it sets the width of the content area, but if box-sizing
is set to border-box
, it sets the width of the border area.
Try it
The specified value of width
applies to the content area so long as its value remains within the values defined by min-width
and max-width
.
- If the value for
width
is less than the value formin-width
, thenmin-width
overrideswidth
. - If the value for
width
is greater than the value formax-width
, thenmax-width
overrideswidth
.
Note: As a geometric property, width
also applies to the <svg>
, <rect>
, <image>
, and <foreignObject>
SVG elements, with auto
resolving to 100%
for <svg>
and 0
for other elements, and percent values being relative to the SVG viewport width for <rect>
. The CSS width
property value overrides any SVG width
attribute value set on the SVG element.
Syntax
/* <length> values */
width: 300px;
width: 25em;
width: anchor-size(--myAnchor inline, 120%);
width: minmax(100px, anchor-size(width));
/* <percentage> value */
width: 75%;
/* Keyword values */
width: max-content;
width: min-content;
width: fit-content;
width: fit-content(20em);
width: auto;
width: stretch;
/* Global values */
width: inherit;
width: initial;
width: revert;
width: revert-layer;
width: unset;
Values
<length>
-
Defines the width as a distance value.
<percentage>
-
Defines the width as a percentage of the containing block's width.
auto
-
The browser will calculate and select a width for the specified element.
max-content
-
The intrinsic preferred width.
min-content
-
The intrinsic minimum width.
fit-content
-
Use the available space, but not more than max-content, i.e.
min(max-content, max(min-content, stretch))
. fit-content(
<length-percentage>
)-
Uses the fit-content formula with the available space replaced by the specified argument, i.e.
min(max-content, max(min-content, <length-percentage>))
. stretch
-
Sets the width of the element's margin box to the width of its containing block. It attempts to make the margin box fill the available space in the containing block, so in a way behaving similar to
100%
but applying the resulting size to the margin box rather than the box determined by box-sizing.Note: To check aliases used by browsers for the
stretch
value and its implementation status, see the Browser compatibility section.
Accessibility
Ensure that elements set with a width
aren't truncated and/or don't obscure other content when the page is zoomed to increase text size.
Formal definition
Initial value | auto |
---|---|
Applies to | all elements but non-replaced inline elements, table rows, and row groups |
Inherited | no |
Percentages | refer to the width of the containing block |
Computed value | a percentage or auto or the absolute length |
Animation type | a length, percentage or calc(); |
Formal syntax
width =
auto |
<length-percentage [0,∞]> |
min-content |
max-content |
fit-content( <length-percentage [0,∞]> ) |
<calc-size()> |
<anchor-size()>
<length-percentage> =
<length> |
<percentage>
<calc-size()> =
calc-size( <calc-size-basis> , <calc-sum> )
<anchor-size()> =
anchor-size( [ <anchor-name> || <anchor-size> ]? , <length-percentage>? )
<calc-size-basis> =
<intrinsic-size-keyword> |
<calc-size()> |
any |
<calc-sum>
<calc-sum> =
<calc-product> [ [ '+' | '-' ] <calc-product> ]*
<anchor-name> =
<dashed-ident>
<anchor-size> =
width |
height |
block |
inline |
self-block |
self-inline
<calc-product> =
<calc-value> [ [ '*' | '/' ] <calc-value> ]*
<calc-value> =
<number> |
<dimension> |
<percentage> |
<calc-keyword> |
( <calc-sum> )
<calc-keyword> =
e |
pi |
infinity |
-infinity |
NaN
Examples
Default width
p.goldie {
background: gold;
}
<p class="goldie">The MDN community writes really great documentation.</p>
Example using pixels and ems
.px_length {
width: 200px;
background-color: red;
color: white;
border: 1px solid black;
}
.em_length {
width: 20em;
background-color: white;
color: red;
border: 1px solid black;
}
<div class="px_length">Width measured in px</div>
<div class="em_length">Width measured in em</div>
Example with percentage
.percent {
width: 20%;
background-color: silver;
border: 1px solid red;
}
<div class="percent">Width in percentage</div>
Example using "max-content"
p.max-green {
background: lightgreen;
width: max-content;
}
<p class="max-green">The MDN community writes really great documentation.</p>
Example using "min-content"
p.min-blue {
background: lightblue;
width: min-content;
}
<p class="min-blue">The MDN community writes really great documentation.</p>
Specifications
Specification |
---|
CSS Box Sizing Module Level 4 # width-height-keywords |
CSS Box Sizing Module Level 4 # sizing-values |
Browser compatibility
BCD tables only load in the browser