rgba()

The rgba() functional notation expresses a color according to its red, green, and blue components. An optional alpha component represents the color's transparency.

Try it

Note: CSS Colors Level 4 allows for space-separated in addition to comma-separated values.

Syntax

rgba(255, 255, 255) /* white */
rgba(255, 255, 255, .5) /* white with 50% opacity */
rgba(255 255 255 / 0.5); /* CSS Colors 4 space-separated values */

Values

Functional notation: rgba(R, G, B[, A])

R (red), G (green), and B (blue) can be either <number>s or <percentage>s, where the number 255 corresponds to 100%. A (alpha) can be a <number> between 0 and 1, or a <percentage>, where the number 1 corresponds to 100% (full opacity).

Functional notation: rgba(R G B[ / A])

CSS Colors Level 4 adds support for space-separated values in the functional notation.

Specifications

Specification
CSS Color Module Level 4
# rgb-functions

Browser compatibility

Desktop Mobile
Chrome Edge Firefox Internet Explorer Opera Safari WebView Android Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet
rgba
1
12
3
9
10
3.1
≤37
18
4
10.1
2
1.0
float_values
66
79
52
No
53
12.1
66
66
52
47
12.2
9.0
space_separated_parameters
65
79
52
No
52
12.1
65
65
52
47
12.2
9.0

https://developer.mozilla.org/en-US/docs/Web/CSS/color_value/rgba