#B51E2A
Closest named color: Firebrick (#B22222). oklch(50.1% 0.184 23.8), rgb(181, 30, 42).
Aa
White text reads best on this color (6.59:1).
About this color
#B51E2A is a medium-dark, vivid red. In OKLCH its lightness is 50%, its chroma 0.184 and its hue 24°. Its hue sits on the warm side of the wheel. The nearest named color is Firebrick (#B22222), ΔE 0.011 away. White text reads best on it, at 6.59:1.
| Hue family | Reds |
| Lightness | medium-dark (50%) |
| Chroma | vivid (0.184) |
| Temperature | warm |
| Nearest name | Firebrick (#B22222) |
| Black text | 3.18:1 |
| White text | 6.59:1 |
Values
| HEX | #B51E2A |
| RGB | rgb(181, 30, 42) |
| HSL | hsl(355, 72%, 41%) |
| OKLCH | oklch(50.1% 0.184 23.8) |
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 #B51E2A | 6.59:1 | AA | Lc -86.0 | Fine for body text |
| Black text on #B51E2A | 3.18:1 | AA large text | Lc 23.2 | Dividers and decoration only |
| #B51E2A text on white | 6.59:1 | AA | Lc 80.9 | Fine for body text |
| #B51E2A text on black | 3.18:1 | AA large text | Lc -21.0 | 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
#F9CDC9
oklch(88.5% 0.05 24.2)
-
Step 300
300
#F5AAA5
oklch(80.9% 0.089 23.5)
-
Step 400
400
#EC7974
oklch(70.6% 0.143 23.9)
-
Step 500
500
#E25051
oklch(63% 0.182 23.6)
-
Step 600
600
#CE2A35
oklch(55.6% 0.198 23.6)
-
Step 700
700 (this color)
#B51E2A
oklch(50.1% 0.184 23.8)
-
Step 800
800
#901A22
oklch(42.7% 0.152 23.6)
-
Step 900
900
#741F20
oklch(37.8% 0.119 24.3)
-
Step 950
950
#441413
oklch(27% 0.075 24.6)
#B51E2A 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) | #504829 | 0.201 |
| Deuteranopia (no green cones) | #746824 | 0.184 |
| Tritanopia (no blue cones) | #C80025 | 0.037 |
| Achromatopsia (no color) | #5D5D5D | 0.186 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #B51E2A
#B51E2A
oklch(50.1% 0.184 23.8)
- #00717A
#00717A
oklch(50% 0.085 204.5)
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 #B51E2A, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Firebrick #B22222 ΔE 0.011
- Scarlet #BE0119 ΔE 0.022
- Rufous #AE2012 ΔE 0.025
- Lipstick Red #C0022F ΔE 0.026
- Brown #A52A2A ΔE 0.032
- Rose Red #BE013C ΔE 0.034
- Rouge #AB1239 ΔE 0.035
- Rusty Red #AF2F0D ΔE 0.036
Use #B51E2A 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.