#631F03
Closest named color: Reddy Brown (#6E1005). oklch(34.3% 0.105 39.6), rgb(99, 31, 3).
Aa
White text reads best on this color (12.15:1).
About this color
#631F03 is a dark, moderately saturated red. In OKLCH its lightness is 34%, its chroma 0.105 and its hue 40°. Its hue sits on the warm side of the wheel. The nearest named color is Reddy Brown (#6E1005), ΔE 0.031 away. White text reads best on it, at 12.15:1.
| Hue family | Reds |
| Lightness | dark (34%) |
| Chroma | moderately saturated (0.105) |
| Temperature | warm |
| Nearest name | Reddy Brown (#6E1005) |
| Black text | 1.72:1 |
| White text | 12.15:1 |
Values
| HEX | #631F03 |
| RGB | rgb(99, 31, 3) |
| HSL | hsl(18, 94%, 20%) |
| OKLCH | oklch(34.3% 0.105 39.6) |
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 #631F03 | 12.15:1 | AAA | Lc -100.5 | Preferred for body text |
| Black text on #631F03 | 1.72:1 | Fails | Lc 0.0 | Not readable |
| #631F03 text on white | 12.15:1 | AAA | Lc 96.9 | Preferred for body text |
| #631F03 text on black | 1.72:1 | 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
#FCF3F0
oklch(97% 0.011 39.4)
-
Step 100
100
#F8E5DF
oklch(93.5% 0.022 38.3)
-
Step 200
200
#F4D0C4
oklch(88.5% 0.044 39.3)
-
Step 300
300
#EEB09B
oklch(81% 0.079 39.5)
-
Step 400
400
#E28463
oklch(70.7% 0.125 40)
-
Step 500
500
#D76035
oklch(63% 0.161 39.6)
-
Step 600
600
#C34203
oklch(55.6% 0.175 39.5)
-
Step 700
700
#A53600
oklch(49% 0.155 39.6)
-
Step 800
800
#882C01
oklch(42.7% 0.134 39.9)
-
Step 900
900 (this color)
#631F03
oklch(34.3% 0.105 39.6)
-
Step 950
950
#41190B
oklch(27.1% 0.067 39.3)
#631F03 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) | #332C00 | 0.104 |
| Deuteranopia (no green cones) | #443B00 | 0.093 |
| Tritanopia (no blue cones) | #6E0A1A | 0.047 |
| Achromatopsia (no color) | #363636 | 0.105 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #631F03
#631F03
oklch(34.3% 0.105 39.6)
- #00404F
#00404F
oklch(34.4% 0.062 219.7)
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 #631F03, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Reddy Brown #6E1005 ΔE 0.031
- Chestnut #742802 ΔE 0.045
- Blood #770001 ΔE 0.050
- Claret #680018 ΔE 0.052
- Maroon #800000 ΔE 0.065
- Burgundy #610023 ΔE 0.069
- Wine Red #7B0323 ΔE 0.071
- Bordeaux #7B002C ΔE 0.081
Use #631F03 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.