#B4101E
Closest named color: Firebrick (#B22222). oklch(49% 0.192 25.5), rgb(180, 16, 30).
Aa
White text reads best on this color (6.92:1).
About this color
#B4101E is a medium-dark, vivid red. In OKLCH its lightness is 49%, its chroma 0.192 and its hue 25°. Its hue sits on the warm side of the wheel. The nearest named color is Firebrick (#B22222), ΔE 0.014 away. White text reads best on it, at 6.92:1.
| Hue family | Reds |
| Lightness | medium-dark (49%) |
| Chroma | vivid (0.192) |
| Temperature | warm |
| Nearest name | Firebrick (#B22222) |
| Black text | 3.03:1 |
| White text | 6.92:1 |
Values
| HEX | #B4101E |
| RGB | rgb(180, 16, 30) |
| HSL | hsl(355, 84%, 38%) |
| OKLCH | oklch(49% 0.192 25.5) |
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 #B4101E | 6.92:1 | AA | Lc -86.9 | Fine for body text |
| Black text on #B4101E | 3.03:1 | AA large text | Lc 22.3 | Dividers and decoration only |
| #B4101E text on white | 6.92:1 | AA | Lc 81.8 | Fine for body text |
| #B4101E text on black | 3.03:1 | AA large text | Lc -20.1 | 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
#FEF2F1
oklch(97% 0.013 23.2)
-
Step 100
100
#FCE3E1
oklch(93.6% 0.028 23.2)
-
Step 200
200
#FACDC8
oklch(88.6% 0.052 25.6)
-
Step 300
300
#F7A9A2
oklch(80.8% 0.093 25)
-
Step 400
400
#EF7870
oklch(70.8% 0.148 25.5)
-
Step 500
500
#E54D4A
oklch(63% 0.189 25.3)
-
Step 600
600
#D1242C
oklch(55.6% 0.206 25.4)
-
Step 700
700 (this color)
#B4101E
oklch(49% 0.192 25.5)
-
Step 800
800
#92151B
oklch(42.6% 0.158 25.5)
-
Step 900
900
#761C1C
oklch(37.8% 0.124 25.5)
-
Step 950
950
#451311
oklch(27% 0.077 26)
#B4101E 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) | #4C441C | 0.211 |
| Deuteranopia (no green cones) | #726615 | 0.192 |
| Tritanopia (no blue cones) | #C70019 | 0.038 |
| Achromatopsia (no color) | #5A5A5A | 0.193 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #B4101E
#B4101E
oklch(49% 0.192 25.5)
- #006E77
#006E77
oklch(49.1% 0.084 204.7)
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 #B4101E, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Firebrick #B22222 ΔE 0.014
- Scarlet #BE0119 ΔE 0.020
- Rufous #AE2012 ΔE 0.020
- Lipstick Red #C0022F ΔE 0.030
- Brown #A52A2A ΔE 0.033
- Rust Red #AA2704 ΔE 0.034
- Rouge #AB1239 ΔE 0.036
- Rusty Red #AF2F0D ΔE 0.037
Use #B4101E 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.