height

The height CSS property specifies the height of an element. By default, the property defines the height of the content area. If box-sizing is set to border-box, however, it instead determines the height of the border area.

The min-height and max-height properties override height.

Syntax

/* Keyword value */
height: auto;

/* <length> values */
height: 120px;
height: 10em;

/* <percentage> value */
height: 75%;

/* Global values */
height: inherit;
height: initial;
height: unset;

Values

<length>

Defines the height as an absolute value.

<percentage>

Defines the height as a percentage of the containing block's height.

auto

The browser will calculate and select a height for the specified element.

max-content

The intrinsic preferred height.

min-content

The intrinsic minimum height.

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, )).

Accessibility concerns

Ensure that elements set with a height are not truncated and/or do not obscure other content when the page is zoomed to increase text size.

• MDN Understanding WCAG, Guideline 1.4 explanations
• Understanding Success Criterion 1.4.4 | W3C Understanding WCAG 2.0

Formal definition

Formal syntax

auto | <length> | <percentage> | min-content | max-content | fit-content(<length-percentage>)
where 
<length-percentage> = <length> | <percentage>

Examples

Setting height using pixels and percentages

HTML

<div id="taller">I'm 50 pixels tall.</div>
<div id="shorter">I'm 25 pixels tall.</div>
<div id="parent">
  <div id="child">
    I'm half the height of my parent.
  </div>
</div>

CSS

div {
  width: 250px;
  margin-bottom: 5px;
  border: 2px solid blue;
}

#taller {
  height: 50px;
}

#shorter {
  height: 25px;
}

#parent {
  height: 100px;
}

#child {
  height: 50%;
  width: 75%;
}

Result

Specifications

Browser compatibility

See also

• The box model, box-sizing
• max-height, min-height
• The mapped logical properties: block-size, inline-size