#663D74
Closest named color: Dark Slate Blue (#483D8B). oklch(43.2% 0.1 317.1), rgb(102, 61, 116).
Aa
White text reads best on this color (8.45:1).
About this color
#663D74 is a dark, moderately saturated purple. In OKLCH its lightness is 43%, its chroma 0.100 and its hue 317°. Its hue sits between the warm and cool halves of the wheel. The nearest named color is Dark Slate Blue (#483D8B), ΔE 0.067 away. White text reads best on it, at 8.45:1.
| Hue family | Purples |
| Lightness | dark (43%) |
| Chroma | moderately saturated (0.100) |
| Temperature | in between |
| Nearest name | Dark Slate Blue (#483D8B) |
| Black text | 2.48:1 |
| White text | 8.45:1 |
Values
| HEX | #663D74 |
| RGB | rgb(102, 61, 116) |
| HSL | hsl(285, 31%, 35%) |
| OKLCH | oklch(43.2% 0.1 317.1) |
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 #663D74 | 8.45:1 | AAA | Lc -93.5 | Preferred for body text |
| Black text on #663D74 | 2.48:1 | Fails | Lc 15.1 | Dividers and decoration only |
| #663D74 text on white | 8.45:1 | AAA | Lc 88.9 | Fine for body text |
| #663D74 text on black | 2.48:1 | Fails | Lc -13.3 | 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
#F8F4F9
oklch(97.2% 0.008 319.4)
-
Step 100
100
#EFE7F1
oklch(93.7% 0.016 319.4)
-
Step 200
200
#E2D3E8
oklch(88.5% 0.033 316.4)
-
Step 300
300
#D0B5DA
oklch(80.8% 0.059 316.9)
-
Step 400
400
#B88EC7
oklch(70.6% 0.093 317)
-
Step 500
500
#A671B9
oklch(63% 0.12 316.8)
-
Step 600
600
#9159A5
oklch(55.6% 0.129 316.7)
-
Step 700
700
#7C488D
oklch(49.1% 0.121 317.4)
-
Step 800
800 (this color)
#663D74
oklch(43.2% 0.1 317.1)
-
Step 900
900
#52335D
oklch(37.6% 0.079 316.8)
-
Step 950
950
#301E36
oklch(26.9% 0.05 317.4)
#663D74 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) | #334A76 | 0.086 |
| Deuteranopia (no green cones) | #3F4E72 | 0.077 |
| Tritanopia (no blue cones) | #664553 | 0.065 |
| Achromatopsia (no color) | #4D4D4D | 0.100 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #663D74
#663D74
oklch(43.2% 0.1 317.1)
- #345C21
#345C21
oklch(43.1% 0.099 136.9)
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 #663D74, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Slate Blue #483D8B ΔE 0.067
- Twilight #4E518B ΔE 0.068
- Rebecca Purple #663399 ΔE 0.068
- Dusk #4E5481 ΔE 0.070
- Dusty Grape #545775 ΔE 0.076
- Light Eggplant #894585 ΔE 0.076
- Brownish Purple #76424E ΔE 0.076
- Blueberry #464196 ΔE 0.079
Use #663D74 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.