line-height-step

Limited availability

This feature is not Baseline because it does not work in some of the most widely-used browsers.

Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

The line-height-step CSS property sets the step unit for line box heights. When the property is set, line box heights are rounded up to the closest multiple of the unit.

Syntax

css
/* Point values */
line-height-step: 18pt;

/* Global values */
line-height-step: inherit;
line-height-step: initial;
line-height-step: revert;
line-height-step: revert-layer;
line-height-step: unset;

The line-height-step property is specified as any one of the following:

  • a <length>.

Values

<length>

The specified <length> is used in the calculation of the line box height step.

Formal definition

Initial value0
Applies toblock containers
Inheritedyes
Computed valueabsolute <length>
Animation typeby computed value type

Formal syntax

line-height-step = 
<length [0,∞]>

Examples

Setting step unit for line box height

In the following example, the height of line box in each paragraph is rounded up to the step unit. The line box in <h1> does not fit into one step unit and thus occupies two, but it is still centered within the two step unit.

css
:root {
  font-size: 12pt;
  --my-grid: 18pt;
  line-height-step: var(--my-grid);
}
h1 {
  font-size: 20pt;
  margin-top: calc(2 * var(--my-grid));
}

The result of these rules is shown below in the following screenshot:

How the line-height-step property affects the appearance of text.

Specifications

Specification
CSS Rhythmic Sizing
# line-height-step

Browser compatibility

Report problems with this compatibility data on GitHub
desktopmobile
Chrome
Edge
Firefox
Opera
Safari
Chrome Android
Firefox for Android
Opera Android
Safari on iOS
Samsung Internet
WebView Android
WebView on iOS
line-height-step
Experimental

Legend

Tip: you can click/tap on a cell for more information.

No support
No support
Experimental. Expect behavior to change in the future.
User must explicitly enable this feature.

See also