#643A9C
Closest named color: Rebecca Purple (#663399). oklch(45% 0.153 300), rgb(100, 58, 156).
Aa
White text reads best on this color (7.99:1).
About this color
#643A9C is a medium-dark, vivid purple. In OKLCH its lightness is 45%, its chroma 0.153 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 0.015 away. White text reads best on it, at 7.99:1.
| Hue family | Purples |
| Lightness | medium-dark (45%) |
| Chroma | vivid (0.153) |
| Temperature | in between |
| Nearest name | Rebecca Purple (#663399) |
| Black text | 2.62:1 |
| White text | 7.99:1 |
Values
| HEX | #643A9C |
| RGB | rgb(100, 58, 156) |
| HSL | hsl(266, 46%, 42%) |
| OKLCH | oklch(45% 0.153 300) |
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 #643A9C | 7.99:1 | AAA | Lc -92.0 | Preferred for body text |
| Black text on #643A9C | 2.62:1 | Fails | Lc 16.7 | Dividers and decoration only |
| #643A9C text on white | 7.99:1 | AAA | Lc 87.3 | Fine for body text |
| #643A9C text on black | 2.62:1 | Fails | Lc -14.9 | 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
#F6F4FD
oklch(97.1% 0.012 296.4)
-
Step 100
100
#ECE6F9
oklch(93.5% 0.026 300.3)
-
Step 200
200
#DED2F6
oklch(88.5% 0.051 300.6)
-
Step 300
300
#C9B4F2
oklch(80.9% 0.089 299.9)
-
Step 400
400
#AF8AEC
oklch(70.7% 0.143 300.2)
-
Step 500
500
#9C69E6
oklch(63.1% 0.184 300)
-
Step 600
600
#884DD4
oklch(55.7% 0.199 300.1)
-
Step 700
700
#733CB8
oklch(49.1% 0.186 299.9)
-
Step 800
800 (this color)
#643A9C
oklch(45% 0.153 300)
-
Step 900
900
#4C2E76
oklch(37.6% 0.119 299.9)
-
Step 950
950
#2D1C45
oklch(27.1% 0.075 300.6)
#643A9C 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) | #00509F | 0.115 |
| Deuteranopia (no green cones) | #15509A | 0.109 |
| Tritanopia (no blue cones) | #584F65 | 0.117 |
| Achromatopsia (no color) | #515151 | 0.154 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #643A9C
#643A9C
oklch(45% 0.153 300)
- #4E5D00
#4E5D00
oklch(45% 0.107 120)
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 #643A9C, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Rebecca Purple #663399 ΔE 0.015
- Blueberry #464196 ΔE 0.054
- Dark Slate Blue #483D8B ΔE 0.057
- Bluey Purple #6241C7 ΔE 0.070
- Twilight #4E518B ΔE 0.074
- Blue With A Hint Of Purple #533CC6 ΔE 0.075
- Grape #7209B7 ΔE 0.076
- Chrysanthemum #560BAD ΔE 0.080
Use #643A9C 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.