Web platform features explorer

rex unit

The rex CSS length unit is a font-relative length that is equal to the x-height of the root element.

Status

Baseline Newly Available (since 2026-01-13)

This feature is expected to reach Baseline Widely Available status on: 2028-07-13

MDN documentation

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 147 Released on 2026-01-13
  • Firefox for Android 147 Released on 2026-01-13
  • Safari 17.2 Released on 2023-12-11
  • Safari on iOS 17.2 Released on 2023-12-11

Developer signals

Votes: 0

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