#663D9C
Closest named color: Rebecca Purple (#663399). oklch(45.7% 0.149 300.5), rgb(102, 61, 156).
Aa
White text reads best on this color (7.74:1).
About this color
#663D9C is a medium-dark, vivid purple. In OKLCH its lightness is 46%, its chroma 0.149 and its hue 300°. Its hue sits between the warm and cool halves of the wheel. The nearest named color is Rebecca Purple (#663399), ΔE 0.022 away. White text reads best on it, at 7.74:1.
| Hue family | Purples |
| Lightness | medium-dark (46%) |
| Chroma | vivid (0.149) |
| Temperature | in between |
| Nearest name | Rebecca Purple (#663399) |
| Black text | 2.71:1 |
| White text | 7.74:1 |
Values
| HEX | #663D9C |
| RGB | rgb(102, 61, 156) |
| HSL | hsl(266, 44%, 43%) |
| OKLCH | oklch(45.7% 0.149 300.5) |
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 #663D9C | 7.74:1 | AAA | Lc -91.3 | Preferred for body text |
| Black text on #663D9C | 2.71:1 | Fails | Lc 17.5 | Dividers and decoration only |
| #663D9C text on white | 7.74:1 | AAA | Lc 86.5 | Fine for body text |
| #663D9C text on black | 2.71:1 | Fails | Lc -15.6 | 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
#F6F4FC
oklch(97.1% 0.011 297.6)
-
Step 100
100
#ECE6F9
oklch(93.5% 0.026 300.3)
-
Step 200
200
#DED2F5
oklch(88.4% 0.049 301)
-
Step 300
300
#C9B4F1
oklch(80.9% 0.087 300.2)
-
Step 400
400
#AF8BEA
oklch(70.8% 0.139 300.3)
-
Step 500
500
#9C6AE3
oklch(63.1% 0.179 300.4)
-
Step 600
600
#884ED1
oklch(55.6% 0.194 300.6)
-
Step 700
700
#733EB5
oklch(49.1% 0.18 300.3)
-
Step 800
800 (this color)
#663D9C
oklch(45.7% 0.149 300.5)
-
Step 900
900
#4C2F75
oklch(37.7% 0.116 300)
-
Step 950
950
#2D1C44
oklch(27% 0.073 301.3)
#663D9C 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) | #04529F | 0.114 |
| Deuteranopia (no green cones) | #1E529A | 0.104 |
| Tritanopia (no blue cones) | #5B5166 | 0.114 |
| Achromatopsia (no color) | #535353 | 0.150 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #663D9C
#663D9C
oklch(45.7% 0.149 300.5)
- #4F5F00
#4F5F00
oklch(45.6% 0.109 120.4)
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 #663D9C, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Rebecca Purple #663399 ΔE 0.022
- Blueberry #464196 ΔE 0.056
- Dark Slate Blue #483D8B ΔE 0.060
- Bluey Purple #6241C7 ΔE 0.069
- Twilight #4E518B ΔE 0.070
- Blue With A Hint Of Purple #533CC6 ΔE 0.076
- Grape #7209B7 ΔE 0.080
- Light Eggplant #894585 ΔE 0.084
Use #663D9C 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.