#663F98
Closest named color: Rebecca Purple (#663399). oklch(45.7% 0.141 301.2), rgb(102, 63, 152).
Aa
White text reads best on this color (7.69:1).
About this color
#663F98 is a medium-dark, vivid purple. In OKLCH its lightness is 46%, its chroma 0.141 and its hue 301°. Its hue sits between the warm and cool halves of the wheel. The nearest named color is Rebecca Purple (#663399), ΔE 0.026 away. White text reads best on it, at 7.69:1.
| Hue family | Purples |
| Lightness | medium-dark (46%) |
| Chroma | vivid (0.141) |
| Temperature | in between |
| Nearest name | Rebecca Purple (#663399) |
| Black text | 2.72:1 |
| White text | 7.69:1 |
Values
| HEX | #663F98 |
| RGB | rgb(102, 63, 152) |
| HSL | hsl(266, 41%, 42%) |
| OKLCH | oklch(45.7% 0.141 301.2) |
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 #663F98 | 7.69:1 | AAA | Lc -91.2 | Preferred for body text |
| Black text on #663F98 | 2.72:1 | Fails | Lc 17.6 | Dividers and decoration only |
| #663F98 text on white | 7.69:1 | AAA | Lc 86.4 | Fine for body text |
| #663F98 text on black | 2.72:1 | Fails | Lc -15.7 | 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
#ECE6F8
oklch(93.5% 0.025 301.1)
-
Step 200
200
#DED3F3
oklch(88.6% 0.045 301.1)
-
Step 300
300
#CAB5EE
oklch(81% 0.082 301.4)
-
Step 400
400
#AF8CE5
oklch(70.7% 0.131 301.2)
-
Step 500
500
#9C6CDE
oklch(63.1% 0.169 301.1)
-
Step 600
600
#8851CB
oklch(55.7% 0.183 301.5)
-
Step 700
700
#7341B0
oklch(49.2% 0.17 301.1)
-
Step 800
800 (this color)
#663F98
oklch(45.7% 0.141 301.2)
-
Step 900
900
#4C3072
oklch(37.7% 0.11 300.8)
-
Step 950
950
#2D1D43
oklch(27.1% 0.07 301.3)
#663F98 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) | #16539B | 0.107 |
| Deuteranopia (no green cones) | #275396 | 0.097 |
| Tritanopia (no blue cones) | #5C5165 | 0.107 |
| Achromatopsia (no color) | #535353 | 0.142 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #663F98
#663F98
oklch(45.7% 0.141 301.2)
- #4E6000
#4E6000
oklch(45.7% 0.11 121.5)
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 #663F98, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Rebecca Purple #663399 ΔE 0.026
- Blueberry #464196 ΔE 0.055
- Dark Slate Blue #483D8B ΔE 0.058
- Twilight #4E518B ΔE 0.064
- Bluey Purple #6241C7 ΔE 0.075
- Light Eggplant #894585 ΔE 0.079
- Dusk #4E5481 ΔE 0.080
- Blue With A Hint Of Purple #533CC6 ΔE 0.083
Use #663F98 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.