#643F37
Closest named color: Purple Brown (#673A3F). oklch(40.9% 0.054 32.8), rgb(100, 63, 55).
Aa
White text reads best on this color (9.09:1).
About this color
#643F37 is a dark, muted red. In OKLCH its lightness is 41%, its chroma 0.054 and its hue 33°. Its hue sits on the warm side of the wheel. The nearest named color is Purple Brown (#673A3F), ΔE 0.023 away. White text reads best on it, at 9.09:1.
| Hue family | Reds |
| Lightness | dark (41%) |
| Chroma | muted (0.054) |
| Temperature | warm |
| Nearest name | Purple Brown (#673A3F) |
| Black text | 2.30:1 |
| White text | 9.09:1 |
Values
| HEX | #643F37 |
| RGB | rgb(100, 63, 55) |
| HSL | hsl(11, 29%, 30%) |
| OKLCH | oklch(40.9% 0.054 32.8) |
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 #643F37 | 9.09:1 | AAA | Lc -95.2 | Preferred for body text |
| Black text on #643F37 | 2.30:1 | Fails | Lc 13.2 | Not readable |
| #643F37 text on white | 9.09:1 | AAA | Lc 90.8 | Preferred for body text |
| #643F37 text on black | 2.30:1 | Fails | Lc -11.5 | 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 800.
-
Step 50
50
#F8F4F4
oklch(97% 0.004 17.2)
-
Step 100
100
#F0E8E6
oklch(93.7% 0.009 34.3)
-
Step 200
200
#E4D5D2
oklch(88.4% 0.017 31.1)
-
Step 300
300
#D4BAB4
oklch(80.9% 0.031 33.1)
-
Step 400
400
#BE968D
oklch(70.8% 0.05 32.9)
-
Step 500
500
#AD7B70
oklch(63% 0.065 32.8)
-
Step 600
600
#986459
oklch(55.6% 0.07 32.5)
-
Step 700
700
#825349
oklch(49.2% 0.066 32.6)
-
Step 800
800 (this color)
#643F37
oklch(40.9% 0.054 32.8)
-
Step 900
900
#563933
oklch(37.6% 0.043 32.1)
-
Step 950
950
#32221E
oklch(27% 0.026 34.5)
#643F37 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) | #474436 | 0.054 |
| Deuteranopia (no green cones) | #504B37 | 0.049 |
| Tritanopia (no blue cones) | #6C3A3D | 0.024 |
| Achromatopsia (no color) | #484848 | 0.055 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #643F37
#643F37
oklch(40.9% 0.054 32.8)
- #21525B
#21525B
oklch(40.9% 0.054 211.4)
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 #643F37, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Purple Brown #673A3F ΔE 0.023
- Brownish Purple #76424E ΔE 0.051
- Mud Brown #60460F ΔE 0.058
- Chestnut #742802 ΔE 0.067
- Charcoal Grey #3C4142 ΔE 0.072
- Milk Chocolate #7F4E1E ΔE 0.080
- Red Brown #8B2E16 ΔE 0.082
- Rust Brown #8B3103 ΔE 0.085
Use #643F37 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.