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rlh unit

Widely Available (since 2026-05-21)

The rlh CSS length unit is a font-relative length relative to the line height of root element.

Browser support

  • Chrome 111 Released on 2023-03-07
  • Chrome Android 111 Released on 2023-03-07
  • Edge 111 Released on 2023-03-13
  • Firefox 120 Released on 2023-11-21
  • Firefox for Android 120 Released on 2023-11-21
  • Safari 16.4 Released on 2023-03-27
  • Safari on iOS 16.4 Released on 2023-03-27

MDN documentation

Specifications

Usage (according to Chrome Platform Status)

~0.005% of page loads. More data at chromestatus.com.

Web Platform Tests (WPT)

View the latest WPT test results for this feature

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