#631B1B
Closest named color: Reddy Brown (#6E1005). oklch(34% 0.104 24.5), rgb(99, 27, 27).
Aa
White text reads best on this color (12.33:1).
About this color
#631B1B is a dark, moderately saturated red. In OKLCH its lightness is 34%, its chroma 0.104 and its hue 25°. Its hue sits on the warm side of the wheel. The nearest named color is Reddy Brown (#6E1005), ΔE 0.029 away. White text reads best on it, at 12.33:1.
| Hue family | Reds |
| Lightness | dark (34%) |
| Chroma | moderately saturated (0.104) |
| Temperature | warm |
| Nearest name | Reddy Brown (#6E1005) |
| Black text | 1.70:1 |
| White text | 12.33:1 |
Values
| HEX | #631B1B |
| RGB | rgb(99, 27, 27) |
| HSL | hsl(0, 57%, 25%) |
| OKLCH | oklch(34% 0.104 24.5) |
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 #631B1B | 12.33:1 | AAA | Lc -100.8 | Preferred for body text |
| Black text on #631B1B | 1.70:1 | Fails | Lc 0.0 | Not readable |
| #631B1B text on white | 12.33:1 | AAA | Lc 97.2 | Preferred for body text |
| #631B1B text on black | 1.70:1 | Fails | Lc 0.0 | Not readable |
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 900.
-
Step 50
50
#FCF3F2
oklch(97.1% 0.01 25.1)
-
Step 100
100
#F9E4E2
oklch(93.5% 0.023 24.1)
-
Step 200
200
#F5CFCB
oklch(88.6% 0.043 25.1)
-
Step 300
300
#EFADA8
oklch(80.8% 0.078 23.8)
-
Step 400
400
#E48079
oklch(70.8% 0.125 24.9)
-
Step 500
500
#D95B57
oklch(63.1% 0.16 24.6)
-
Step 600
600
#C43C3D
oklch(55.6% 0.173 24.4)
-
Step 700
700
#A92D2F
oklch(49.1% 0.16 24.6)
-
Step 800
800
#892727
oklch(42.6% 0.133 24.8)
-
Step 900
900 (this color)
#631B1B
oklch(34% 0.104 24.5)
-
Step 950
950
#411716
oklch(27% 0.066 23.9)
#631B1B 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) | #2F2B1A | 0.112 |
| Deuteranopia (no green cones) | #413A19 | 0.102 |
| Tritanopia (no blue cones) | #6D071C | 0.030 |
| Achromatopsia (no color) | #353535 | 0.104 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #631B1B
#631B1B
oklch(34% 0.104 24.5)
- #004046
#004046
oklch(33.9% 0.058 205.3)
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 #631B1B, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Reddy Brown #6E1005 ΔE 0.029
- Claret #680018 ΔE 0.032
- Burgundy #610023 ΔE 0.045
- Blood #770001 ΔE 0.047
- Wine Red #7B0323 ΔE 0.056
- Chestnut #742802 ΔE 0.058
- Bordeaux #7B002C ΔE 0.062
- Maroon #800000 ΔE 0.063
Use #631B1B 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.