#B31D33
Closest named color: Firebrick (#B22222). oklch(49.8% 0.182 20.3), rgb(179, 29, 51).
Aa
White text reads best on this color (6.68:1).
About this color
#B31D33 is a medium-dark, vivid red. In OKLCH its lightness is 50%, its chroma 0.182 and its hue 20°. Its hue sits on the warm side of the wheel. The nearest named color is Firebrick (#B22222), ΔE 0.021 away. White text reads best on it, at 6.68:1.
| Hue family | Reds |
| Lightness | medium-dark (50%) |
| Chroma | vivid (0.182) |
| Temperature | warm |
| Nearest name | Firebrick (#B22222) |
| Black text | 3.14:1 |
| White text | 6.68:1 |
Values
| HEX | #B31D33 |
| RGB | rgb(179, 29, 51) |
| HSL | hsl(351, 72%, 41%) |
| OKLCH | oklch(49.8% 0.182 20.3) |
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 #B31D33 | 6.68:1 | AA | Lc -86.4 | Fine for body text |
| Black text on #B31D33 | 3.14:1 | AA large text | Lc 22.8 | Dividers and decoration only |
| #B31D33 text on white | 6.68:1 | AA | Lc 81.3 | Fine for body text |
| #B31D33 text on black | 3.14:1 | AA large text | Lc -20.6 | 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
#FDF2F2
oklch(97% 0.012 17.4)
-
Step 100
100
#FBE4E3
oklch(93.7% 0.025 20.6)
-
Step 200
200
#F8CDCC
oklch(88.5% 0.049 19.7)
-
Step 300
300
#F5AAA9
oklch(81% 0.089 20)
-
Step 400
400
#EB797B
oklch(70.6% 0.141 20.2)
-
Step 500
500
#E25059
oklch(63.2% 0.181 20.5)
-
Step 600
600
#CD2B3F
oklch(55.6% 0.196 20.5)
-
Step 700
700 (this color)
#B31D33
oklch(49.8% 0.182 20.3)
-
Step 800
800
#8F1A29
oklch(42.6% 0.151 20.4)
-
Step 900
900
#731F26
oklch(37.7% 0.117 20.3)
-
Step 950
950
#441416
oklch(27% 0.074 21.1)
#B31D33 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) | #4D4832 | 0.202 |
| Deuteranopia (no green cones) | #72672E | 0.184 |
| Tritanopia (no blue cones) | #C50027 | 0.036 |
| Achromatopsia (no color) | #5C5C5C | 0.184 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #B31D33
#B31D33
oklch(49.8% 0.182 20.3)
- #007176
#007176
oklch(49.9% 0.085 200.2)
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 #B31D33, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Firebrick #B22222 ΔE 0.021
- Rouge #AB1239 ΔE 0.025
- Lipstick Red #C0022F ΔE 0.026
- Rose Red #BE013C ΔE 0.028
- Scarlet #BE0119 ΔE 0.030
- Brown #A52A2A ΔE 0.032
- Rufous #AE2012 ΔE 0.033
- Raspberry #B00149 ΔE 0.043
Use #B31D33 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.