#B31B2B
Closest named color: Firebrick (#B22222). oklch(49.5% 0.184 22.9), rgb(179, 27, 43).
Aa
White text reads best on this color (6.75:1).
About this color
#B31B2B is a medium-dark, vivid red. In OKLCH its lightness is 50%, its chroma 0.184 and its hue 23°. Its hue sits on the warm side of the wheel. The nearest named color is Firebrick (#B22222), ΔE 0.013 away. White text reads best on it, at 6.75:1.
| Hue family | Reds |
| Lightness | medium-dark (50%) |
| Chroma | vivid (0.184) |
| Temperature | warm |
| Nearest name | Firebrick (#B22222) |
| Black text | 3.10:1 |
| White text | 6.75:1 |
Values
| HEX | #B31B2B |
| RGB | rgb(179, 27, 43) |
| HSL | hsl(354, 74%, 40%) |
| OKLCH | oklch(49.5% 0.184 22.9) |
Contrast
WCAG 2 contrast ratios are the conformance target: AA needs 4.5:1 for body text and 3:1 for large text, AAA needs 7:1. APCA Lc values are supplementary guidance from the WCAG 3 drafts.
| Pair | WCAG 2 | Result | APCA | APCA guidance |
|---|---|---|---|---|
| White text on #B31B2B | 6.75:1 | AA | Lc -86.6 | Fine for body text |
| Black text on #B31B2B | 3.10:1 | AA large text | Lc 22.6 | Dividers and decoration only |
| #B31B2B text on white | 6.75:1 | AA | Lc 81.5 | Fine for body text |
| #B31B2B text on black | 3.10:1 | AA large text | Lc -20.4 | Dividers and decoration only |
Tints and shades
A 50–950 scale built in OKLCH: the hue is held, lightness follows a Tailwind v4-like curve, and every step is kept inside the sRGB gamut. This color sits at step 700.
-
Step 50
50
#FDF3F2
oklch(97.2% 0.011 24.3)
-
Step 100
100
#FBE4E2
oklch(93.7% 0.025 23.6)
-
Step 200
200
#F9CDCA
oklch(88.5% 0.05 22.7)
-
Step 300
300
#F5AAA6
oklch(80.9% 0.089 22.6)
-
Step 400
400
#EC7976
oklch(70.7% 0.143 22.9)
-
Step 500
500
#E25053
oklch(63% 0.182 22.8)
-
Step 600
600
#CE2A37
oklch(55.6% 0.198 23)
-
Step 700
700 (this color)
#B31B2B
oklch(49.5% 0.184 22.9)
-
Step 800
800
#901A24
oklch(42.7% 0.152 22.8)
-
Step 900
900
#741E22
oklch(37.7% 0.119 22.6)
-
Step 950
950
#441414
oklch(27% 0.074 23.5)
#B31B2B with color blindness
Simulated with the Machado et al. (2009) model. ΔE is how far the color moves: below about 0.02 you would not notice a change.
| Vision | Seen as | Shift (ΔE) |
|---|---|---|
| Protanopia (no red cones) | #4E472A | 0.202 |
| Deuteranopia (no green cones) | #726725 | 0.186 |
| Tritanopia (no blue cones) | #C50023 | 0.035 |
| Achromatopsia (no color) | #5B5B5B | 0.186 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #B31B2B
#B31B2B
oklch(49.5% 0.184 22.9)
- #007077
#007077
oklch(49.6% 0.084 202.4)
Analogous
Neighbouring hues, 30° either side.
Split complementary
The two hues beside the complement (150° and 210°).
Triadic
Three hues spaced 120° apart.
Palettes with this color
Curated palettes that contain a color within ΔE 0.04 (OKLab) of #B31B2B, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Firebrick #B22222 ΔE 0.013
- Scarlet #BE0119 ΔE 0.025
- Rufous #AE2012 ΔE 0.025
- Lipstick Red #C0022F ΔE 0.027
- Rouge #AB1239 ΔE 0.029
- Brown #A52A2A ΔE 0.030
- Rose Red #BE013C ΔE 0.034
- Rust Red #AA2704 ΔE 0.038
Use #B31B2B in your product
Turn it into light and dark UI roles checked for contrast, then export to Tailwind v4, shadcn/ui, CSS or design tokens.