#643A78
Closest named color: Rebecca Purple (#663399). oklch(42.6% 0.109 313.9), rgb(100, 58, 120).
Aa
White text reads best on this color (8.68:1).
About this color
#643A78 is a dark, moderately saturated purple. In OKLCH its lightness is 43%, its chroma 0.109 and its hue 314°. Its hue sits between the warm and cool halves of the wheel. The nearest named color is Rebecca Purple (#663399), ΔE 0.058 away. White text reads best on it, at 8.68:1.
| Hue family | Purples |
| Lightness | dark (43%) |
| Chroma | moderately saturated (0.109) |
| Temperature | in between |
| Nearest name | Rebecca Purple (#663399) |
| Black text | 2.41:1 |
| White text | 8.68:1 |
Values
| HEX | #643A78 |
| RGB | rgb(100, 58, 120) |
| HSL | hsl(281, 35%, 35%) |
| OKLCH | oklch(42.6% 0.109 313.9) |
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 #643A78 | 8.68:1 | AAA | Lc -94.0 | Preferred for body text |
| Black text on #643A78 | 2.41:1 | Fails | Lc 14.5 | Not readable |
| #643A78 text on white | 8.68:1 | AAA | Lc 89.5 | Fine for body text |
| #643A78 text on black | 2.41:1 | Fails | Lc -12.7 | 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
#F7F4FA
oklch(97.1% 0.009 308.4)
-
Step 100
100
#EEE6F3
oklch(93.5% 0.019 312.8)
-
Step 200
200
#E2D3EA
oklch(88.6% 0.035 314.1)
-
Step 300
300
#D0B5DE
oklch(80.9% 0.064 314.1)
-
Step 400
400
#B88DCD
oklch(70.7% 0.102 314.3)
-
Step 500
500
#A670C0
oklch(63.2% 0.13 314.1)
-
Step 600
600
#9156AC
oklch(55.5% 0.142 314.3)
-
Step 700
700
#7B4694
oklch(49.1% 0.132 313.9)
-
Step 800
800 (this color)
#643A78
oklch(42.6% 0.109 313.9)
-
Step 900
900
#523261
oklch(37.7% 0.086 314.2)
-
Step 950
950
#301E39
oklch(27.1% 0.054 313.8)
#643A78 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) | #2C497A | 0.093 |
| Deuteranopia (no green cones) | #394C76 | 0.082 |
| Tritanopia (no blue cones) | #624453 | 0.075 |
| Achromatopsia (no color) | #4B4B4B | 0.110 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #643A78
#643A78
oklch(42.6% 0.109 313.9)
- #345B13
#345B13
oklch(42.6% 0.109 134)
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 #643A78, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Rebecca Purple #663399 ΔE 0.058
- Dark Slate Blue #483D8B ΔE 0.060
- Twilight #4E518B ΔE 0.070
- Blueberry #464196 ΔE 0.072
- Dusk #4E5481 ΔE 0.075
- Light Eggplant #894585 ΔE 0.081
- Dusty Grape #545775 ΔE 0.084
- Brownish Purple #76424E ΔE 0.088
Use #643A78 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.