#663F94
Closest named color: Rebecca Purple (#663399). oklch(45.5% 0.136 302.5), rgb(102, 63, 148).
Aa
White text reads best on this color (7.76:1).
About this color
#663F94 is a medium-dark, moderately saturated purple. In OKLCH its lightness is 45%, its chroma 0.136 and its hue 302°. Its hue sits between the warm and cool halves of the wheel. The nearest named color is Rebecca Purple (#663399), ΔE 0.028 away. White text reads best on it, at 7.76:1.
| Hue family | Purples |
| Lightness | medium-dark (45%) |
| Chroma | moderately saturated (0.136) |
| Temperature | in between |
| Nearest name | Rebecca Purple (#663399) |
| Black text | 2.70:1 |
| White text | 7.76:1 |
Values
| HEX | #663F94 |
| RGB | rgb(102, 63, 148) |
| HSL | hsl(268, 40%, 41%) |
| OKLCH | oklch(45.5% 0.136 302.5) |
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 #663F94 | 7.76:1 | AAA | Lc -91.4 | Preferred for body text |
| Black text on #663F94 | 2.70:1 | Fails | Lc 17.4 | Dividers and decoration only |
| #663F94 text on white | 7.76:1 | AAA | Lc 86.7 | Fine for body text |
| #663F94 text on black | 2.70:1 | Fails | Lc -15.4 | Dividers and decoration only |
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
#DED3F2
oklch(88.5% 0.044 301.7)
-
Step 300
300
#CAB5EC
oklch(80.9% 0.079 302.1)
-
Step 400
400
#B08CE2
oklch(70.7% 0.128 302.5)
-
Step 500
500
#9D6DDA
oklch(63.1% 0.163 302.3)
-
Step 600
600
#8952C7
oklch(55.6% 0.177 302.7)
-
Step 700
700
#7442AC
oklch(49.2% 0.164 302.5)
-
Step 800
800 (this color)
#663F94
oklch(45.5% 0.136 302.5)
-
Step 900
900
#4D316F
oklch(37.8% 0.105 302.5)
-
Step 950
950
#2D1D41
oklch(27% 0.067 302.7)
#663F94 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) | #1C5297 | 0.104 |
| Deuteranopia (no green cones) | #2B5292 | 0.094 |
| Tritanopia (no blue cones) | #5D5063 | 0.103 |
| Achromatopsia (no color) | #525252 | 0.137 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #663F94
#663F94
oklch(45.5% 0.136 302.5)
- #4C6000
#4C6000
oklch(45.6% 0.111 122.6)
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 #663F94, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Rebecca Purple #663399 ΔE 0.028
- Blueberry #464196 ΔE 0.056
- Dark Slate Blue #483D8B ΔE 0.056
- Twilight #4E518B ΔE 0.062
- Light Eggplant #894585 ΔE 0.076
- Dusk #4E5481 ΔE 0.077
- Bluey Purple #6241C7 ΔE 0.082
- Blue With A Hint Of Purple #533CC6 ΔE 0.089
Use #663F94 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.