Web features explorer

rcap unit

Newly Available (since 2026-01-13)
Expected to be Widely Available on 2028-07-13

The rcap CSS length unit is a font-relative length equal to the value of the cap unit on the root element. Cap-height is approximately equal to the height of a capital Latin letter.

Browser support

  • Chrome 118 Released on 2023-10-10
  • Chrome Android 118 Released on 2023-10-10
  • Edge 118 Released on 2023-10-13
  • 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

MDN documentation

Specifications

Usage (according to Chrome Platform Status)

~0.002% 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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