#B10817
Closest named color: Rufous (#AE2012). oklch(48.1% 0.192 26.4), rgb(177, 8, 23).
Aa
White text reads best on this color (7.20:1).
About this color
#B10817 is a medium-dark, vivid red. In OKLCH its lightness is 48%, its chroma 0.192 and its hue 26°. Its hue sits on the warm side of the wheel. The nearest named color is Rufous (#AE2012), ΔE 0.019 away. White text reads best on it, at 7.20:1.
| Hue family | Reds |
| Lightness | medium-dark (48%) |
| Chroma | vivid (0.192) |
| Temperature | warm |
| Nearest name | Rufous (#AE2012) |
| Black text | 2.91:1 |
| White text | 7.20:1 |
Values
| HEX | #B10817 |
| RGB | rgb(177, 8, 23) |
| HSL | hsl(355, 91%, 36%) |
| OKLCH | oklch(48.1% 0.192 26.4) |
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 #B10817 | 7.20:1 | AAA | Lc -87.7 | Fine for body text |
| Black text on #B10817 | 2.91:1 | Fails | Lc 21.4 | Dividers and decoration only |
| #B10817 text on white | 7.20:1 | AAA | Lc 82.6 | Fine for body text |
| #B10817 text on black | 2.91:1 | Fails | Lc -19.3 | 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
#FCE4E0
oklch(93.7% 0.027 28.9)
-
Step 200
200
#FACDC7
oklch(88.6% 0.052 27)
-
Step 300
300
#F7AAA1
oklch(81% 0.092 26.7)
-
Step 400
400
#EF786E
oklch(70.8% 0.148 26.4)
-
Step 500
500
#E64D47
oklch(63.2% 0.19 26.4)
-
Step 600
600
#D12428
oklch(55.6% 0.206 26.4)
-
Step 700
700 (this color)
#B10817
oklch(48.1% 0.192 26.4)
-
Step 800
800
#931519
oklch(42.8% 0.16 26.2)
-
Step 900
900
#761C1A
oklch(37.7% 0.125 26.5)
-
Step 950
950
#451310
oklch(27% 0.078 27)
#B10817 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) | #4A4114 | 0.211 |
| Deuteranopia (no green cones) | #70630B | 0.190 |
| Tritanopia (no blue cones) | #C40013 | 0.039 |
| Achromatopsia (no color) | #575757 | 0.194 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #B10817
#B10817
oklch(48.1% 0.192 26.4)
- #006B75
#006B75
oklch(48.2% 0.082 206.1)
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 #B10817, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Rufous #AE2012 ΔE 0.019
- Firebrick #B22222 ΔE 0.020
- Scarlet #BE0119 ΔE 0.027
- Rust Red #AA2704 ΔE 0.032
- Brown #A52A2A ΔE 0.033
- Rouge #AB1239 ΔE 0.037
- Lipstick Red #C0022F ΔE 0.038
- Rusty Red #AF2F0D ΔE 0.039
Use #B10817 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.