#663E37
Closest named color: Purple Brown (#673A3F). oklch(40.9% 0.058 30.5), rgb(102, 62, 55).
Aa
White text reads best on this color (9.09:1).
About this color
#663E37 is a dark, muted red. In OKLCH its lightness is 41%, its chroma 0.058 and its hue 31°. Its hue sits on the warm side of the wheel. The nearest named color is Purple Brown (#673A3F), ΔE 0.020 away. White text reads best on it, at 9.09:1.
| Hue family | Reds |
| Lightness | dark (41%) |
| Chroma | muted (0.058) |
| Temperature | warm |
| Nearest name | Purple Brown (#673A3F) |
| Black text | 2.30:1 |
| White text | 9.09:1 |
Values
| HEX | #663E37 |
| RGB | rgb(102, 62, 55) |
| HSL | hsl(9, 30%, 31%) |
| OKLCH | oklch(40.9% 0.058 30.5) |
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 #663E37 | 9.09:1 | AAA | Lc -95.2 | Preferred for body text |
| Black text on #663E37 | 2.30:1 | Fails | Lc 13.2 | Not readable |
| #663E37 text on white | 9.09:1 | AAA | Lc 90.8 | Preferred for body text |
| #663E37 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
#E5D5D2
oklch(88.5% 0.018 30.3)
-
Step 300
300
#D6B9B4
oklch(80.9% 0.034 29.4)
-
Step 400
400
#C0958C
oklch(70.8% 0.054 32)
-
Step 500
500
#AF7A70
oklch(63.1% 0.069 31)
-
Step 600
600
#9B6258
oklch(55.6% 0.076 30.5)
-
Step 700
700
#845148
oklch(49.1% 0.071 30.6)
-
Step 800
800 (this color)
#663E37
oklch(40.9% 0.058 30.5)
-
Step 900
900
#573933
oklch(37.8% 0.044 31.7)
-
Step 950
950
#33211E
oklch(26.9% 0.029 29.6)
#663E37 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) | #474336 | 0.058 |
| Deuteranopia (no green cones) | #514C36 | 0.055 |
| Tritanopia (no blue cones) | #6E383C | 0.025 |
| Achromatopsia (no color) | #484848 | 0.058 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #663E37
#663E37
oklch(40.9% 0.058 30.5)
- #1C535C
#1C535C
oklch(41% 0.058 210.2)
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 #663E37, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Purple Brown #673A3F ΔE 0.020
- Brownish Purple #76424E ΔE 0.048
- Mud Brown #60460F ΔE 0.061
- Chestnut #742802 ΔE 0.064
- Charcoal Grey #3C4142 ΔE 0.075
- Red Brown #8B2E16 ΔE 0.079
- Milk Chocolate #7F4E1E ΔE 0.080
- Rust Brown #8B3103 ΔE 0.082
Use #663E37 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.