#663C8D
Closest named color: Rebecca Purple (#663399). oklch(44.5% 0.132 305.6), rgb(102, 60, 141).
Aa
White text reads best on this color (8.08:1).
About this color
#663C8D is a dark, moderately saturated purple. In OKLCH its lightness is 45%, its chroma 0.132 and its hue 306°. Its hue sits between the warm and cool halves of the wheel. The nearest named color is Rebecca Purple (#663399), ΔE 0.029 away. White text reads best on it, at 8.08:1.
| Hue family | Purples |
| Lightness | dark (45%) |
| Chroma | moderately saturated (0.132) |
| Temperature | in between |
| Nearest name | Rebecca Purple (#663399) |
| Black text | 2.59:1 |
| White text | 8.08:1 |
Values
| HEX | #663C8D |
| RGB | rgb(102, 60, 141) |
| HSL | hsl(271, 40%, 39%) |
| OKLCH | oklch(44.5% 0.132 305.6) |
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 #663C8D | 8.08:1 | AAA | Lc -92.4 | Preferred for body text |
| Black text on #663C8D | 2.59:1 | Fails | Lc 16.3 | Dividers and decoration only |
| #663C8D text on white | 8.08:1 | AAA | Lc 87.7 | Fine for body text |
| #663C8D text on black | 2.59:1 | Fails | Lc -14.5 | 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
#F7F4FB
oklch(97.1% 0.01 305.4)
-
Step 100
100
#EDE6F6
oklch(93.5% 0.023 305.6)
-
Step 200
200
#E0D2F0
oklch(88.4% 0.043 306.5)
-
Step 300
300
#CDB4E9
oklch(80.9% 0.078 306.1)
-
Step 400
400
#B38CDE
oklch(70.7% 0.123 305.3)
-
Step 500
500
#A16CD4
oklch(63% 0.158 305.9)
-
Step 600
600
#8C52C2
oklch(55.7% 0.172 305.4)
-
Step 700
700
#7742A7
oklch(49.2% 0.159 305.5)
-
Step 800
800 (this color)
#663C8D
oklch(44.5% 0.132 305.6)
-
Step 900
900
#4F306C
oklch(37.6% 0.103 305.9)
-
Step 950
950
#2E1D3F
oklch(27% 0.064 305.6)
#663C8D 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) | #1E4E90 | 0.105 |
| Deuteranopia (no green cones) | #2E508B | 0.095 |
| Tritanopia (no blue cones) | #604B5E | 0.096 |
| Achromatopsia (no color) | #505050 | 0.133 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #663C8D
#663C8D
oklch(44.5% 0.132 305.6)
- #455E00
#455E00
oklch(44.5% 0.113 125.5)
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 #663C8D, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Rebecca Purple #663399 ΔE 0.029
- Dark Slate Blue #483D8B ΔE 0.054
- Blueberry #464196 ΔE 0.058
- Twilight #4E518B ΔE 0.065
- Light Eggplant #894585 ΔE 0.076
- Dusk #4E5481 ΔE 0.078
- Purple #800080 ΔE 0.091
- Warm Purple #952E8F ΔE 0.092
Use #663C8D 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.