#663E7B
Closest named color: Rebecca Purple (#663399). oklch(43.8% 0.106 313), rgb(102, 62, 123).
Aa
White text reads best on this color (8.26:1).
About this color
#663E7B is a dark, moderately saturated purple. In OKLCH its lightness is 44%, its chroma 0.106 and its hue 313°. Its hue sits between the warm and cool halves of the wheel. The nearest named color is Rebecca Purple (#663399), ΔE 0.058 away. White text reads best on it, at 8.26:1.
| Hue family | Purples |
| Lightness | dark (44%) |
| Chroma | moderately saturated (0.106) |
| Temperature | in between |
| Nearest name | Rebecca Purple (#663399) |
| Black text | 2.54:1 |
| White text | 8.26:1 |
Values
| HEX | #663E7B |
| RGB | rgb(102, 62, 123) |
| HSL | hsl(279, 33%, 36%) |
| OKLCH | oklch(43.8% 0.106 313) |
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 #663E7B | 8.26:1 | AAA | Lc -93.0 | Preferred for body text |
| Black text on #663E7B | 2.54:1 | Fails | Lc 15.7 | Dividers and decoration only |
| #663E7B text on white | 8.26:1 | AAA | Lc 88.3 | Fine for body text |
| #663E7B text on black | 2.54:1 | Fails | Lc -13.8 | 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
#F7F4F9
oklch(97.1% 0.007 312.3)
-
Step 100
100
#EEE7F3
oklch(93.7% 0.018 311.6)
-
Step 200
200
#E1D3EA
oklch(88.5% 0.035 312.4)
-
Step 300
300
#CFB5DE
oklch(80.8% 0.063 313.2)
-
Step 400
400
#B68ECD
oklch(70.6% 0.1 312.8)
-
Step 500
500
#A471C0
oklch(63.1% 0.127 312.8)
-
Step 600
600
#8F58AC
oklch(55.6% 0.138 312.9)
-
Step 700
700
#7A4794
oklch(49.1% 0.129 313.1)
-
Step 800
800 (this color)
#663E7B
oklch(43.8% 0.106 313)
-
Step 900
900
#513361
oklch(37.7% 0.084 313)
-
Step 950
950
#2F1E39
oklch(26.9% 0.053 312.1)
#663E7B 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) | #314C7D | 0.088 |
| Deuteranopia (no green cones) | #3C4F79 | 0.079 |
| Tritanopia (no blue cones) | #644756 | 0.073 |
| Achromatopsia (no color) | #4E4E4E | 0.107 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #663E7B
#663E7B
oklch(43.8% 0.106 313)
- #395E18
#395E18
oklch(43.8% 0.107 133.3)
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 #663E7B, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Rebecca Purple #663399 ΔE 0.058
- Dark Slate Blue #483D8B ΔE 0.061
- Twilight #4E518B ΔE 0.062
- Dusk #4E5481 ΔE 0.067
- Blueberry #464196 ΔE 0.071
- Light Eggplant #894585 ΔE 0.072
- Dusty Grape #545775 ΔE 0.076
- Brownish Purple #76424E ΔE 0.085
Use #663E7B 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.