Percentage opacity

Adds support for percentage values to the opacity properties, specifically, opacity, stop-opacity, fill-opacity, and stroke-opacity. For example, opacity: 50%; is equivalent to opacity: 0.5; 'opacity' ( 'stop-opacity' ( 'fill-opacity' ( 'stroke-opacity' (

This brings consistency and spec compliance. The rgba() function already accepts percentage alpha value, for example rgba(0, 255, 0, 50%).



Working draft or equivalent

Status in Chromium


In development (tracking bug)

Consensus & Standardization

After a feature ships in Chrome, the values listed here are not guaranteed to be up to date.


Last updated on 2019-06-27