Indigo is the CSS named color #4B0082 — rgb(75, 0, 130), hsl(275, 100%, 25%). Its relative luminance is 0.031, giving 12.95:1 against white and 1.62:1 against black, so it works as a text color on white.
| HEX | #4B0082 |
|---|---|
| RGB | rgb(75, 0, 130) |
| HSL | hsl(275, 100%, 25%) |
| Relative luminance | 0.0311 |
| Contrast on white | 12.95:1 AA pass |
| Contrast on black | 1.62:1 AA fail |
Built by mixing indigo toward white (four steps) and toward black (four steps) while keeping the hue. Use the shades generator for a different step count or to add harmony sets.
Closest by CIELAB distance (ΔE76). For perceptual matching in a design system, compare in OKLab before locking a token.
indigo is #4B0082, which is rgb(75, 0, 130) and hsl(275, 100%, 25%). It is one of the 148 CSS named colors defined by the CSS Color Module Level 4.
Indigo has a relative luminance of 0.031 on a 0–1 scale, so it is a dark color. Against white it scores 12.95:1; against black, 1.62:1.
indigo reaches 12.95:1 against white, which clears WCAG 2.2 AA for normal text (4.5:1) at any size.