#643B9B
Closest named color: Rebecca Purple (#663399). oklch(45.1% 0.151 300.1), rgb(100, 59, 155).
Aa
White text reads best on this color (7.95:1).
About this color
#643B9B is a medium-dark, vivid purple. In OKLCH its lightness is 45%, its chroma 0.151 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 0.017 away. White text reads best on it, at 7.95:1.
| Hue family | Purples |
| Lightness | medium-dark (45%) |
| Chroma | vivid (0.151) |
| Temperature | in between |
| Nearest name | Rebecca Purple (#663399) |
| Black text | 2.64:1 |
| White text | 7.95:1 |
Values
| HEX | #643B9B |
| RGB | rgb(100, 59, 155) |
| HSL | hsl(266, 45%, 42%) |
| OKLCH | oklch(45.1% 0.151 300.1) |
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 #643B9B | 7.95:1 | AAA | Lc -91.9 | Preferred for body text |
| Black text on #643B9B | 2.64:1 | Fails | Lc 16.8 | Dividers and decoration only |
| #643B9B text on white | 7.95:1 | AAA | Lc 87.2 | Fine for body text |
| #643B9B text on black | 2.64:1 | Fails | Lc -15.0 | 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
#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
#C9B4F2
oklch(80.9% 0.089 299.9)
-
Step 400
400
#AF8BEB
oklch(70.8% 0.141 300.1)
-
Step 500
500
#9C6AE4
oklch(63.1% 0.18 300.2)
-
Step 600
600
#874ED2
oklch(55.6% 0.195 299.9)
-
Step 700
700
#733DB6
oklch(49.1% 0.183 300.2)
-
Step 800
800 (this color)
#643B9B
oklch(45.1% 0.151 300.1)
-
Step 900
900
#4C2F75
oklch(37.7% 0.116 300)
-
Step 950
950
#2C1C45
oklch(26.9% 0.075 299.4)
#643B9B 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) | #00519E | 0.114 |
| Deuteranopia (no green cones) | #195099 | 0.106 |
| Tritanopia (no blue cones) | #584F65 | 0.114 |
| Achromatopsia (no color) | #515151 | 0.152 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #643B9B
#643B9B
oklch(45.1% 0.151 300.1)
- #4E5E00
#4E5E00
oklch(45.2% 0.108 120.5)
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 #643B9B, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Rebecca Purple #663399 ΔE 0.017
- Blueberry #464196 ΔE 0.053
- Dark Slate Blue #483D8B ΔE 0.056
- Bluey Purple #6241C7 ΔE 0.071
- Twilight #4E518B ΔE 0.071
- Blue With A Hint Of Purple #533CC6 ΔE 0.076
- Grape #7209B7 ΔE 0.079
- Chrysanthemum #560BAD ΔE 0.083
Use #643B9B 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.