Web/CSS/percentage

The <percentage> CSS data type represents a percentage value. It is often used to define a size as relative to an element's parent object. Numerous properties can use percentages, such as width, height, margin, padding, and font-size.

Note: Only calculated values can be inherited. Thus, even if a percentage value is used on the parent property, a real value (such as a width in pixels for a <length> value) will be accessible on the inherited property, not the percentage value.

Syntax

The <percentage> data type consists of a <number> followed by the percentage sign (%). Optionally, it may be preceded by a single + or - sign, although negative values are not valid for all properties. As with all CSS dimensions, there is no space between the symbol and the number.

Interpolation

When animated, values of the <percentage> data type are interpolated as real, floating-point numbers. The speed of the interpolation is determined by the timing function associated with the animation.

Examples

Width and margin-left

<div style="background-color:navy;">
  <div style="width:50%; margin-left:20%; background-color:chartreuse;">
    Width: 50%, Left margin: 20%
  </div>
  <div style="width:30%; margin-left:60%; background-color:pink;">
    Width: 30%, Left margin: 60%
  </div>
</div>

The above HTML will output:

Font-size

<div style="font-size:18px;">
  <p>Full-size text (18px)</p>
  <p><span style="font-size:50%;">50% (9px)</span></p>
  <p><span style="font-size:200%;">200% (36px)</span></p>
</div>

The above HTML will output:

Specifications

Specification	Status	Comment
CSS Values and Units Module Level 4The definition of '<percentage>' in that specification.	Editor's Draft	No significant change.
CSS Values and Units Module Level 3The definition of '<percentage>' in that specification.	Candidate Recommendation	No significant change from CSS Level 2 (Revision 1).
CSS Level 2 (Revision 1)The definition of '<percentage>' in that specification.	Recommendation	No change from CSS Level 1.
CSS Level 1The definition of '<percentage>' in that specification.	Recommendation	Initial definition.

Browser compatibility

The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.

Update compatibility data on GitHub

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
<percentage>	Chrome Full support 1	Edge Full support 12	Firefox Full support 1	IE Full support 3	Opera Full support 3.5	Safari Full support 1	WebView Android Full support ≤37	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 1.0

Legend

Full support  

Full support

<percentage> by Mozilla Contributors is licensed under CC-BY-SA 2.5.