alpha()
Newly Available (since 2026-09-14)
Expected to be Widely Available on 2029-03-14
The alpha() CSS function computes a relative color value by adjusting the opacity of an origin color.
Browser support
- Chrome 151 Released on 2026-07-28
- Chrome Android 151 Released on 2026-07-28
- Edge 151 Released on 2026-07-31
- Firefox 155 Released on 2026-09-01
- Firefox for Android 155 Released on 2026-09-01
- Safari 27 Released on 2026-09-14
- Safari on iOS 27 Released on 2026-09-14
MDN documentation
Specifications
View as JSON | Edit this feature | Report an issue | Web-features entry: source, dist