#663603
Closest named color: Chestnut (#742802). oklch(38.6% 0.089 59.1), rgb(102, 54, 3).
Aa
White text reads best on this color (10.02:1).
About this color
#663603 is a dark, moderately saturated brown. In OKLCH its lightness is 39%, its chroma 0.089 and its hue 59°. Its hue sits on the warm side of the wheel. The nearest named color is Chestnut (#742802), ΔE 0.040 away. White text reads best on it, at 10.02:1.
| Hue family | Browns |
| Lightness | dark (39%) |
| Chroma | moderately saturated (0.089) |
| Temperature | warm |
| Nearest name | Chestnut (#742802) |
| Black text | 2.09:1 |
| White text | 10.02:1 |
Values
| HEX | #663603 |
| RGB | rgb(102, 54, 3) |
| HSL | hsl(31, 94%, 21%) |
| OKLCH | oklch(38.6% 0.089 59.1) |
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 #663603 | 10.02:1 | AAA | Lc -97.0 | Preferred for body text |
| Black text on #663603 | 2.09:1 | Fails | Lc 11.1 | Not readable |
| #663603 text on white | 10.02:1 | AAA | Lc 92.9 | Preferred for body text |
| #663603 text on black | 2.09:1 | Fails | Lc -9.6 | 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
#FAF4F0
oklch(97.1% 0.008 56.3)
-
Step 100
100
#F4E7DD
oklch(93.6% 0.02 60.2)
-
Step 200
200
#EDD4C1
oklch(88.6% 0.038 59.5)
-
Step 300
300
#E2B796
oklch(80.9% 0.067 59.1)
-
Step 400
400
#D29059
oklch(70.8% 0.107 59.6)
-
Step 500
500
#C57220
oklch(63.2% 0.137 59.2)
-
Step 600
600
#AA5D00
oklch(55.7% 0.131 59.4)
-
Step 700
700
#904D00
oklch(49.1% 0.117 58.7)
-
Step 800
800
#763F00
oklch(42.7% 0.101 59.7)
-
Step 900
900 (this color)
#663603
oklch(38.6% 0.089 59.1)
-
Step 950
950
#3A1F05
oklch(27% 0.056 60.5)
#663603 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) | #453B00 | 0.066 |
| Deuteranopia (no green cones) | #504603 | 0.060 |
| Tritanopia (no blue cones) | #712B2D | 0.062 |
| Achromatopsia (no color) | #424242 | 0.090 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #663603
#663603
oklch(38.6% 0.089 59.1)
- #00496D
#00496D
oklch(38.6% 0.087 239.2)
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 #663603, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Chestnut #742802 ΔE 0.040
- Mud Brown #60460F ΔE 0.043
- Purple Brown #673A3F ΔE 0.067
- Green Brown #544E03 ΔE 0.074
- Reddy Brown #6E1005 ΔE 0.076
- Rust Brown #8B3103 ΔE 0.076
- Red Brown #8B2E16 ΔE 0.079
- Olive Brown #645403 ΔE 0.085
Use #663603 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.