#B4001D
Closest named color: Firebrick (#B22222). oklch(48.5% 0.197 24.6), rgb(180, 0, 29).
Aa
White text reads best on this color (7.09:1).
About this color
#B4001D is a medium-dark, vivid red. In OKLCH its lightness is 49%, its chroma 0.197 and its hue 25°. Its hue sits on the warm side of the wheel. The nearest named color is Firebrick (#B22222), ΔE 0.022 away. White text reads best on it, at 7.09:1.
| Hue family | Reds |
| Lightness | medium-dark (49%) |
| Chroma | vivid (0.197) |
| Temperature | warm |
| Nearest name | Firebrick (#B22222) |
| Black text | 2.95:1 |
| White text | 7.09:1 |
Values
| HEX | #B4001D |
| RGB | rgb(180, 0, 29) |
| HSL | hsl(350, 100%, 35%) |
| OKLCH | oklch(48.5% 0.197 24.6) |
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 #B4001D | 7.09:1 | AAA | Lc -87.0 | Fine for body text |
| Black text on #B4001D | 2.95:1 | Fails | Lc 22.1 | Dividers and decoration only |
| #B4001D text on white | 7.09:1 | AAA | Lc 81.9 | Fine for body text |
| #B4001D text on black | 2.95:1 | Fails | Lc -20.0 | 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
#FEF2F1
oklch(97% 0.013 23.2)
-
Step 100
100
#FCE3E1
oklch(93.6% 0.028 23.2)
-
Step 200
200
#FACCC8
oklch(88.4% 0.053 24)
-
Step 300
300
#F8A9A2
oklch(80.9% 0.094 25)
-
Step 400
400
#F17670
oklch(70.8% 0.153 24.6)
-
Step 500
500
#E74A4A
oklch(63% 0.194 24.6)
-
Step 600
600
#D31D2C
oklch(55.6% 0.211 24.6)
-
Step 700
700 (this color)
#B4001D
oklch(48.5% 0.197 24.6)
-
Step 800
800
#94101C
oklch(42.7% 0.163 24.4)
-
Step 900
900
#771A1C
oklch(37.7% 0.127 24.8)
-
Step 950
950
#461211
oklch(27% 0.08 25.2)
#B4001D 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) | #49411B | 0.218 |
| Deuteranopia (no green cones) | #716413 | 0.196 |
| Tritanopia (no blue cones) | #C70012 | 0.041 |
| Achromatopsia (no color) | #585858 | 0.198 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #B4001D
#B4001D
oklch(48.5% 0.197 24.6)
- #006C75
#006C75
oklch(48.5% 0.083 204.9)
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 #B4001D, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Firebrick #B22222 ΔE 0.022
- Scarlet #BE0119 ΔE 0.022
- Rufous #AE2012 ΔE 0.025
- Lipstick Red #C0022F ΔE 0.031
- Rouge #AB1239 ΔE 0.034
- Brown #A52A2A ΔE 0.037
- Rust Red #AA2704 ΔE 0.039
- Rose Red #BE013C ΔE 0.039
Use #B4001D 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.