#663FA1
Closest named color: Rebecca Purple (#663399). oklch(46.4% 0.153 298.6), rgb(102, 63, 161).
Aa
White text reads best on this color (7.52:1).
About this color
#663FA1 is a medium-dark, vivid purple. In OKLCH its lightness is 46%, its chroma 0.153 and its hue 299°. 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 7.52:1.
| Hue family | Purples |
| Lightness | medium-dark (46%) |
| Chroma | vivid (0.153) |
| Temperature | in between |
| Nearest name | Rebecca Purple (#663399) |
| Black text | 2.79:1 |
| White text | 7.52:1 |
Values
| HEX | #663FA1 |
| RGB | rgb(102, 63, 161) |
| HSL | hsl(264, 44%, 44%) |
| OKLCH | oklch(46.4% 0.153 298.6) |
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 #663FA1 | 7.52:1 | AAA | Lc -90.6 | Preferred for body text |
| Black text on #663FA1 | 2.79:1 | Fails | Lc 18.3 | Dividers and decoration only |
| #663FA1 text on white | 7.52:1 | AAA | Lc 85.8 | Fine for body text |
| #663FA1 text on black | 2.79:1 | Fails | Lc -16.3 | 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 700.
-
Step 50
50
#F6F4FB
oklch(97.1% 0.009 299.2)
-
Step 100
100
#EBE7F7
oklch(93.6% 0.022 297.4)
-
Step 200
200
#DCD4F1
oklch(88.5% 0.04 298.2)
-
Step 300
300
#C6B7EA
oklch(80.9% 0.073 298.2)
-
Step 400
400
#AA90E0
oklch(70.7% 0.117 298.3)
-
Step 500
500
#9672D7
oklch(63.1% 0.15 298.4)
-
Step 600
600
#8158C5
oklch(55.6% 0.164 298.2)
-
Step 700
700 (this color)
#663FA1
oklch(46.4% 0.153 298.6)
-
Step 800
800
#593B8A
oklch(42.7% 0.127 298.4)
-
Step 900
900
#49336E
oklch(37.6% 0.099 298.8)
-
Step 950
950
#2B1F40
oklch(27.1% 0.061 299.1)
#663FA1 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) | #0054A4 | 0.113 |
| Deuteranopia (no green cones) | #1A539F | 0.104 |
| Tritanopia (no blue cones) | #59546A | 0.117 |
| Achromatopsia (no color) | #545454 | 0.154 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #663FA1
#663FA1
oklch(46.4% 0.153 298.6)
- #536100
#536100
oklch(46.4% 0.109 119)
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 #663FA1, 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 0.058
- Bluey Purple #6241C7 ΔE 0.061
- Dark Slate Blue #483D8B ΔE 0.064
- Blue With A Hint Of Purple #533CC6 ΔE 0.070
- Twilight #4E518B ΔE 0.071
- Iris #6258C4 ΔE 0.076
- Blurple #5539CC ΔE 0.077
Use #663FA1 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.