#B4381F
Closest named color: Rusty Red (#AF2F0D). oklch(52% 0.165 33.2), rgb(180, 56, 31).
Aa
White text reads best on this color (5.95:1).
About this color
#B4381F is a medium-dark, vivid red. In OKLCH its lightness is 52%, its chroma 0.165 and its hue 33°. Its hue sits on the warm side of the wheel. The nearest named color is Rusty Red (#AF2F0D), ΔE 0.020 away. White text reads best on it, at 5.95:1.
| Hue family | Reds |
| Lightness | medium-dark (52%) |
| Chroma | vivid (0.165) |
| Temperature | warm |
| Nearest name | Rusty Red (#AF2F0D) |
| Black text | 3.52:1 |
| White text | 5.95:1 |
Values
| HEX | #B4381F |
| RGB | rgb(180, 56, 31) |
| HSL | hsl(10, 71%, 41%) |
| OKLCH | oklch(52% 0.165 33.2) |
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 #B4381F | 5.95:1 | AA | Lc -83.9 | Fine for body text |
| Black text on #B4381F | 3.52:1 | AA large text | Lc 25.4 | Dividers and decoration only |
| #B4381F text on white | 5.95:1 | AA | Lc 78.7 | Fine for body text |
| #B4381F text on black | 3.52:1 | AA large text | Lc -23.1 | 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
#FCF3F1
oklch(97.1% 0.01 32.5)
-
Step 100
100
#F9E5E0
oklch(93.7% 0.023 34.3)
-
Step 200
200
#F5CFC7
oklch(88.5% 0.044 31.9)
-
Step 300
300
#EFAEA0
oklch(80.8% 0.079 32.5)
-
Step 400
400
#E4816B
oklch(70.6% 0.127 33.5)
-
Step 500
500
#DA5D43
oklch(63.2% 0.163 33.4)
-
Step 600
600
#C53D22
oklch(55.5% 0.177 33.1)
-
Step 700
700 (this color)
#B4381F
oklch(52% 0.165 33.2)
-
Step 800
800
#8A2814
oklch(42.7% 0.136 33.3)
-
Step 900
900
#6F2718
oklch(37.8% 0.106 33.5)
-
Step 950
950
#41180F
oklch(27% 0.066 33.9)
#B4381F 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) | #5D521B | 0.170 |
| Deuteranopia (no green cones) | #7B6E19 | 0.156 |
| Tritanopia (no blue cones) | #C60A33 | 0.060 |
| Achromatopsia (no color) | #646464 | 0.165 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #B4381F
#B4381F
oklch(52% 0.165 33.2)
- #007688
#007688
oklch(52% 0.091 213)
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 #B4381F, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Rusty Red #AF2F0D ΔE 0.020
- Sinopia #BB3E03 ΔE 0.025
- Firebrick #B22222 ΔE 0.034
- Dull Red #BB3F3F ΔE 0.035
- Rust Red #AA2704 ΔE 0.037
- Rufous #AE2012 ΔE 0.038
- Brick #A03623 ΔE 0.042
- Russet #A13905 ΔE 0.042
Use #B4381F 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.