#643B89
Closest named color: Rebecca Purple (#663399). oklch(43.9% 0.128 306.1), rgb(100, 59, 137).
Aa
White text reads best on this color (8.30:1).
About this color
#643B89 is a dark, moderately saturated purple. In OKLCH its lightness is 44%, its chroma 0.128 and its hue 306°. Its hue sits between the warm and cool halves of the wheel. The nearest named color is Rebecca Purple (#663399), ΔE 0.033 away. White text reads best on it, at 8.30:1.
| Hue family | Purples |
| Lightness | dark (44%) |
| Chroma | moderately saturated (0.128) |
| Temperature | in between |
| Nearest name | Rebecca Purple (#663399) |
| Black text | 2.52:1 |
| White text | 8.30:1 |
Values
| HEX | #643B89 |
| RGB | rgb(100, 59, 137) |
| HSL | hsl(272, 40%, 38%) |
| OKLCH | oklch(43.9% 0.128 306.1) |
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 #643B89 | 8.30:1 | AAA | Lc -93.0 | Preferred for body text |
| Black text on #643B89 | 2.52:1 | Fails | Lc 15.6 | Dividers and decoration only |
| #643B89 text on white | 8.30:1 | AAA | Lc 88.4 | Fine for body text |
| #643B89 text on black | 2.52:1 | Fails | Lc -13.8 | 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
#F7F4FB
oklch(97.1% 0.01 305.4)
-
Step 100
100
#EDE6F6
oklch(93.5% 0.023 305.6)
-
Step 200
200
#E0D3F0
oklch(88.6% 0.042 305.8)
-
Step 300
300
#CCB5E8
oklch(80.9% 0.075 305.3)
-
Step 400
400
#B38CDC
oklch(70.7% 0.121 305.9)
-
Step 500
500
#A16DD2
oklch(63.1% 0.154 306.2)
-
Step 600
600
#8C53BF
oklch(55.6% 0.167 306.1)
-
Step 700
700
#7743A5
oklch(49.2% 0.155 306)
-
Step 800
800 (this color)
#643B89
oklch(43.9% 0.128 306.1)
-
Step 900
900
#4F316B
oklch(37.7% 0.1 306.1)
-
Step 950
950
#2E1D3F
oklch(27% 0.064 305.6)
#643B89 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) | #204D8C | 0.102 |
| Deuteranopia (no green cones) | #2E4E87 | 0.092 |
| Tritanopia (no blue cones) | #5E4A5C | 0.094 |
| Achromatopsia (no color) | #4E4E4E | 0.129 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #643B89
#643B89
oklch(43.9% 0.128 306.1)
- #435C00
#435C00
oklch(43.8% 0.111 125.8)
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 #643B89, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Rebecca Purple #663399 ΔE 0.033
- Dark Slate Blue #483D8B ΔE 0.050
- Blueberry #464196 ΔE 0.057
- Twilight #4E518B ΔE 0.064
- Dusk #4E5481 ΔE 0.076
- Light Eggplant #894585 ΔE 0.079
- Purple #800080 ΔE 0.091
- Dusty Grape #545775 ΔE 0.092
Use #643B89 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.