line-height-step

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.

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

Syntax

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

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 typediscrete

Formal syntax

<length>

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.

: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 Status Comment
CSS Rhythmic Sizing
The definition of 'line-height-step' in that specification.
Working Draft Initial definition.

Browser compatibility

DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
line-height-step
Experimental
Chrome Full support 60
Disabled
Full support 60
Disabled
Disabled From version 60: this feature is behind the --enable-blink-features=CSSSnapSize runtime flag.
Edge Full support 79
Disabled
Full support 79
Disabled
Disabled From version 79: this feature is behind the --enable-blink-features=CSSSnapSize runtime flag.
Firefox No support NoIE No support NoOpera Full support 47
Disabled
Full support 47
Disabled
Disabled From version 47: this feature is behind the --enable-blink-features=CSSSnapSize runtime flag.
Safari No support NoWebView Android No support NoChrome Android Full support 60
Disabled
Full support 60
Disabled
Disabled From version 60: this feature is behind the --enable-blink-features=CSSSnapSize runtime flag.
Firefox Android No support NoOpera Android Full support 44
Disabled
Full support 44
Disabled
Disabled From version 44: this feature is behind the --enable-blink-features=CSSSnapSize runtime flag.
Safari iOS No support NoSamsung Internet Android No support No

Legend

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

See also