#663C7E
Closest named color: Rebecca Purple (#663399). oklch(43.6% 0.114 311.9), rgb(102, 60, 126).
Aa
White text reads best on this color (8.35:1).
About this color
#663C7E is a dark, moderately saturated purple. In OKLCH its lightness is 44%, its chroma 0.114 and its hue 312°. Its hue sits between the warm and cool halves of the wheel. The nearest named color is Rebecca Purple (#663399), ΔE 0.051 away. White text reads best on it, at 8.35:1.
| Hue family | Purples |
| Lightness | dark (44%) |
| Chroma | moderately saturated (0.114) |
| Temperature | in between |
| Nearest name | Rebecca Purple (#663399) |
| Black text | 2.51:1 |
| White text | 8.35:1 |
Values
| HEX | #663C7E |
| RGB | rgb(102, 60, 126) |
| HSL | hsl(278, 35%, 36%) |
| OKLCH | oklch(43.6% 0.114 311.9) |
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 #663C7E | 8.35:1 | AAA | Lc -93.2 | Preferred for body text |
| Black text on #663C7E | 2.51:1 | Fails | Lc 15.4 | Dividers and decoration only |
| #663C7E text on white | 8.35:1 | AAA | Lc 88.6 | Fine for body text |
| #663C7E text on black | 2.51:1 | Fails | Lc -13.6 | 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 800.
-
Step 50
50
#F7F4FA
oklch(97.1% 0.009 308.4)
-
Step 100
100
#EEE6F3
oklch(93.5% 0.019 312.8)
-
Step 200
200
#E1D3EB
oklch(88.5% 0.036 311.4)
-
Step 300
300
#CFB5E0
oklch(80.9% 0.066 311.9)
-
Step 400
400
#B78DD1
oklch(70.7% 0.107 312)
-
Step 500
500
#A56FC4
oklch(63.1% 0.136 312.3)
-
Step 600
600
#9056B1
oklch(55.7% 0.147 311.9)
-
Step 700
700
#7A4598
oklch(49% 0.138 311.8)
-
Step 800
800 (this color)
#663C7E
oklch(43.6% 0.114 311.9)
-
Step 900
900
#513263
oklch(37.7% 0.088 312)
-
Step 950
950
#301E3A
oklch(27.1% 0.055 312.7)
#663C7E 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) | #2C4C80 | 0.095 |
| Deuteranopia (no green cones) | #384F7C | 0.086 |
| Tritanopia (no blue cones) | #634757 | 0.079 |
| Achromatopsia (no color) | #4E4E4E | 0.114 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #663C7E
#663C7E
oklch(43.6% 0.114 311.9)
- #395D0C
#395D0C
oklch(43.5% 0.113 131.7)
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 #663C7E, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Rebecca Purple #663399 ΔE 0.051
- Dark Slate Blue #483D8B ΔE 0.059
- Twilight #4E518B ΔE 0.065
- Blueberry #464196 ΔE 0.068
- Dusk #4E5481 ΔE 0.072
- Light Eggplant #894585 ΔE 0.074
- Dusty Grape #545775 ΔE 0.083
- Purple #800080 ΔE 0.092
Use #663C7E 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.