#663F55
Closest named color: Purple Brown (#673A3F). oklch(42.1% 0.063 345.3), rgb(102, 63, 85).
Aa
White text reads best on this color (8.72:1).
About this color
#663F55 is a dark, muted red. In OKLCH its lightness is 42%, its chroma 0.063 and its hue 345°. Its hue sits on the warm side of the wheel. The nearest named color is Purple Brown (#673A3F), ΔE 0.034 away. White text reads best on it, at 8.72:1.
| Hue family | Reds |
| Lightness | dark (42%) |
| Chroma | muted (0.063) |
| Temperature | warm |
| Nearest name | Purple Brown (#673A3F) |
| Black text | 2.40:1 |
| White text | 8.72:1 |
Values
| HEX | #663F55 |
| RGB | rgb(102, 63, 85) |
| HSL | hsl(326, 24%, 32%) |
| OKLCH | oklch(42.1% 0.063 345.3) |
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 #663F55 | 8.72:1 | AAA | Lc -94.3 | Preferred for body text |
| Black text on #663F55 | 2.40:1 | Fails | Lc 14.2 | Not readable |
| #663F55 text on white | 8.72:1 | AAA | Lc 89.8 | Fine for body text |
| #663F55 text on black | 2.40:1 | Fails | Lc -12.5 | 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
#F8F4F6
oklch(97.1% 0.005 345.3)
-
Step 100
100
#EFE7EB
oklch(93.5% 0.01 345.4)
-
Step 200
200
#E4D4DC
oklch(88.5% 0.021 345.7)
-
Step 300
300
#D3B8C6
oklch(81% 0.036 345.3)
-
Step 400
400
#BC92A9
oklch(70.6% 0.059 344.7)
-
Step 500
500
#AB7794
oklch(63.1% 0.076 345)
-
Step 600
600
#965F7E
oklch(55.6% 0.083 345.3)
-
Step 700
700
#804F6A
oklch(49.2% 0.075 346.1)
-
Step 800
800 (this color)
#663F55
oklch(42.1% 0.063 345.3)
-
Step 900
900
#553747
oklch(37.8% 0.049 346.5)
-
Step 950
950
#32202A
oklch(27% 0.032 345.1)
#663F55 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) | #424756 | 0.065 |
| Deuteranopia (no green cones) | #4B4D54 | 0.060 |
| Tritanopia (no blue cones) | #6B3F47 | 0.025 |
| Achromatopsia (no color) | #4B4B4B | 0.063 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #663F55
#663F55
oklch(42.1% 0.063 345.3)
- #275845
#275845
oklch(42% 0.063 165.7)
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 #663F55, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Purple Brown #673A3F ΔE 0.034
- Brownish Purple #76424E ΔE 0.036
- Dusty Grape #545775 ΔE 0.076
- Dark Mauve #874C62 ΔE 0.077
- Charcoal Grey #3C4142 ΔE 0.084
- Dusk #4E5481 ΔE 0.086
- YInMn Blue #415A77 ΔE 0.095
- Twilight #4E518B ΔE 0.097
Use #663F55 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.