#B31F1F
Closest named color: Firebrick (#B22222). oklch(49.6% 0.183 27.1), rgb(179, 31, 31).
Aa
White text reads best on this color (6.70:1).
About this color
#B31F1F is a medium-dark, vivid red. In OKLCH its lightness is 50%, its chroma 0.183 and its hue 27°. Its hue sits on the warm side of the wheel. The nearest named color is Firebrick (#B22222), ΔE 0.003 away. White text reads best on it, at 6.70:1.
| Hue family | Reds |
| Lightness | medium-dark (50%) |
| Chroma | vivid (0.183) |
| Temperature | warm |
| Nearest name | Firebrick (#B22222) |
| Black text | 3.13:1 |
| White text | 6.70:1 |
Values
| HEX | #B31F1F |
| RGB | rgb(179, 31, 31) |
| HSL | hsl(0, 70%, 41%) |
| OKLCH | oklch(49.6% 0.183 27.1) |
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 #B31F1F | 6.70:1 | AA | Lc -86.5 | Fine for body text |
| Black text on #B31F1F | 3.13:1 | AA large text | Lc 22.7 | Dividers and decoration only |
| #B31F1F text on white | 6.70:1 | AA | Lc 81.3 | Fine for body text |
| #B31F1F text on black | 3.13:1 | AA large text | Lc -20.5 | 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
#FDF3F1
oklch(97.1% 0.011 31.1)
-
Step 100
100
#FBE4E1
oklch(93.7% 0.026 26.5)
-
Step 200
200
#F8CEC8
oklch(88.6% 0.048 27.6)
-
Step 300
300
#F5ABA2
oklch(81% 0.089 26.9)
-
Step 400
400
#EC7A6F
oklch(70.7% 0.143 27)
-
Step 500
500
#E25249
oklch(63.1% 0.181 27.1)
-
Step 600
600
#CD2D2B
oklch(55.5% 0.196 27)
-
Step 700
700 (this color)
#B31F1F
oklch(49.6% 0.183 27.1)
-
Step 800
800
#901C1A
oklch(42.7% 0.152 27.2)
-
Step 900
900
#74201C
oklch(37.8% 0.118 27.1)
-
Step 950
950
#441411
oklch(26.9% 0.075 26.9)
#B31F1F 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) | #50471D | 0.199 |
| Deuteranopia (no green cones) | #746717 | 0.180 |
| Tritanopia (no blue cones) | #C60022 | 0.038 |
| Achromatopsia (no color) | #5C5C5C | 0.184 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #B31F1F
#B31F1F
oklch(49.6% 0.183 27.1)
- #006F7B
#006F7B
oklch(49.5% 0.085 207.8)
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 #B31F1F, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Firebrick #B22222 ΔE 0.003
- Rufous #AE2012 ΔE 0.014
- Scarlet #BE0119 ΔE 0.024
- Rusty Red #AF2F0D ΔE 0.027
- Rust Red #AA2704 ΔE 0.027
- Brown #A52A2A ΔE 0.028
- Lipstick Red #C0022F ΔE 0.035
- Rouge #AB1239 ΔE 0.041
Use #B31F1F 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.