#643A88
Closest named color: Rebecca Purple (#663399). oklch(43.6% 0.129 306.7), rgb(100, 58, 136).
Aa
White text reads best on this color (8.39:1).
About this color
#643A88 is a dark, moderately saturated purple. In OKLCH its lightness is 44%, its chroma 0.129 and its hue 307°. 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 8.39:1.
| Hue family | Purples |
| Lightness | dark (44%) |
| Chroma | moderately saturated (0.129) |
| Temperature | in between |
| Nearest name | Rebecca Purple (#663399) |
| Black text | 2.50:1 |
| White text | 8.39:1 |
Values
| HEX | #643A88 |
| RGB | rgb(100, 58, 136) |
| HSL | hsl(272, 40%, 38%) |
| OKLCH | oklch(43.6% 0.129 306.7) |
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 #643A88 | 8.39:1 | AAA | Lc -93.2 | Preferred for body text |
| Black text on #643A88 | 2.50:1 | Fails | Lc 15.4 | Dividers and decoration only |
| #643A88 text on white | 8.39:1 | AAA | Lc 88.6 | Fine for body text |
| #643A88 text on black | 2.50:1 | Fails | Lc -13.6 | 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
#E0D2EF
oklch(88.4% 0.042 307.2)
-
Step 300
300
#CDB4E7
oklch(80.8% 0.075 307)
-
Step 400
400
#B48CDB
oklch(70.7% 0.12 306.8)
-
Step 500
500
#A26DD1
oklch(63.1% 0.153 307)
-
Step 600
600
#8D53BE
oklch(55.7% 0.166 306.8)
-
Step 700
700
#7842A4
oklch(49.1% 0.156 307)
-
Step 800
800 (this color)
#643A88
oklch(43.6% 0.129 306.7)
-
Step 900
900
#4F316B
oklch(37.7% 0.1 306.1)
-
Step 950
950
#2E1D3E
oklch(26.9% 0.063 306.4)
#643A88 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) | #1F4C8B | 0.104 |
| Deuteranopia (no green cones) | #2E4E86 | 0.093 |
| Tritanopia (no blue cones) | #5E495B | 0.094 |
| Achromatopsia (no color) | #4D4D4D | 0.130 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #643A88
#643A88
oklch(43.6% 0.129 306.7)
- #415C00
#415C00
oklch(43.7% 0.112 126.8)
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 #643A88, 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 0.051
- Blueberry #464196 ΔE 0.058
- Twilight #4E518B ΔE 0.066
- Dusk #4E5481 ΔE 0.078
- Light Eggplant #894585 ΔE 0.080
- Purple #800080 ΔE 0.089
- Dusty Grape #545775 ΔE 0.093
Use #643A88 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.