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<percentage> CSS type - CSS | MDN

<percentage> CSS type

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 <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.

In this article

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 easing function associated with the animation.

Examples

Width and margin-left

html
<div class="container"> <div class="box1">Width: 50%, Left margin: 20%</div> <div class="box2">Width: 30%, Left margin: 60%</div> </div>
css
.container { background-color: navy; } .box1 { width: 50%; margin-left: 20%; background-color: chartreuse; } .box2 { width: 30%; margin-left: 60%; background-color: pink; }

Font-size

html
<div class="container"> <p>Full-size text (18px)</p> <p><span class="half">50% (9px)</span></p> <p><span class="double">200% (36px)</span></p> </div>
css
.container { font-size: 18px; } .half { font-size: 50%; } .double { font-size: 200%; }

Specifications

Specification
CSS Values and Units Module Level 4
# percentages

Browser compatibility

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See also