#663990
Closest named color: Rebecca Purple (#663399). oklch(44.3% 0.141 305.2), rgb(102, 57, 144).
Aa
White text reads best on this color (8.22:1).
About this color
#663990 is a dark, vivid purple. In OKLCH its lightness is 44%, its chroma 0.141 and its hue 305°. Its hue sits between the warm and cool halves of the wheel. The nearest named color is Rebecca Purple (#663399), ΔE 0.020 away. White text reads best on it, at 8.22:1.
| Hue family | Purples |
| Lightness | dark (44%) |
| Chroma | vivid (0.141) |
| Temperature | in between |
| Nearest name | Rebecca Purple (#663399) |
| Black text | 2.55:1 |
| White text | 8.22:1 |
Values
| HEX | #663990 |
| RGB | rgb(102, 57, 144) |
| HSL | hsl(271, 43%, 39%) |
| OKLCH | oklch(44.3% 0.141 305.2) |
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 #663990 | 8.22:1 | AAA | Lc -92.7 | Preferred for body text |
| Black text on #663990 | 2.55:1 | Fails | Lc 16.0 | Dividers and decoration only |
| #663990 text on white | 8.22:1 | AAA | Lc 88.0 | Fine for body text |
| #663990 text on black | 2.55:1 | Fails | Lc -14.1 | 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
#F7F4FC
oklch(97.2% 0.011 303.1)
-
Step 100
100
#EDE6F7
oklch(93.5% 0.024 304.5)
-
Step 200
200
#E0D2F2
oklch(88.5% 0.046 305.2)
-
Step 300
300
#CDB4EC
oklch(81% 0.082 305)
-
Step 400
400
#B48AE2
oklch(70.7% 0.132 305.2)
-
Step 500
500
#A26AD9
oklch(63.1% 0.168 305.4)
-
Step 600
600
#8D4FC7
oklch(55.7% 0.182 305)
-
Step 700
700
#783EAC
oklch(49% 0.171 305.2)
-
Step 800
800 (this color)
#663990
oklch(44.3% 0.141 305.2)
-
Step 900
900
#502F6F
oklch(37.8% 0.109 305.6)
-
Step 950
950
#2F1C41
oklch(27% 0.07 306)
#663990 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) | #124D93 | 0.115 |
| Deuteranopia (no green cones) | #274F8E | 0.103 |
| Tritanopia (no blue cones) | #5F4A5F | 0.102 |
| Achromatopsia (no color) | #4F4F4F | 0.142 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #663990
#663990
oklch(44.3% 0.141 305.2)
- #455D00
#455D00
oklch(44.2% 0.111 125.1)
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 #663990, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Rebecca Purple #663399 ΔE 0.020
- Dark Slate Blue #483D8B ΔE 0.055
- Blueberry #464196 ΔE 0.058
- Twilight #4E518B ΔE 0.071
- Light Eggplant #894585 ΔE 0.081
- Dusk #4E5481 ΔE 0.085
- Purple #800080 ΔE 0.087
- Grape #7209B7 ΔE 0.088
Use #663990 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.