#643A8D
Closest named color: Rebecca Purple (#663399). oklch(44% 0.135 304.8), rgb(100, 58, 141).
Aa
White text reads best on this color (8.29:1).
About this color
#643A8D is a dark, moderately saturated purple. In OKLCH its lightness is 44%, its chroma 0.135 and its hue 305°. Its hue sits between the warm and cool halves of the wheel. The nearest named color is Rebecca Purple (#663399), ΔE 0.026 away. White text reads best on it, at 8.29:1.
| Hue family | Purples |
| Lightness | dark (44%) |
| Chroma | moderately saturated (0.135) |
| Temperature | in between |
| Nearest name | Rebecca Purple (#663399) |
| Black text | 2.53:1 |
| White text | 8.29:1 |
Values
| HEX | #643A8D |
| RGB | rgb(100, 58, 141) |
| HSL | hsl(270, 42%, 39%) |
| OKLCH | oklch(44% 0.135 304.8) |
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 #643A8D | 8.29:1 | AAA | Lc -92.9 | Preferred for body text |
| Black text on #643A8D | 2.53:1 | Fails | Lc 15.7 | Dividers and decoration only |
| #643A8D text on white | 8.29:1 | AAA | Lc 88.3 | Fine for body text |
| #643A8D text on black | 2.53:1 | Fails | Lc -13.9 | 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
#F7F4FB
oklch(97.1% 0.01 305.4)
-
Step 100
100
#EDE6F7
oklch(93.5% 0.024 304.5)
-
Step 200
200
#E0D2F1
oklch(88.5% 0.045 305.9)
-
Step 300
300
#CCB4EA
oklch(80.8% 0.079 304.9)
-
Step 400
400
#B38BE0
oklch(70.7% 0.127 305)
-
Step 500
500
#A06CD7
oklch(63.1% 0.162 304.6)
-
Step 600
600
#8C51C4
oklch(55.6% 0.176 305)
-
Step 700
700
#7741A9
oklch(49.1% 0.163 305.1)
-
Step 800
800 (this color)
#643A8D
oklch(44% 0.135 304.8)
-
Step 900
900
#4F306E
oklch(37.8% 0.106 305)
-
Step 950
950
#2E1D40
oklch(27% 0.066 304.8)
#643A8D 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) | #184D90 | 0.108 |
| Deuteranopia (no green cones) | #294E8B | 0.097 |
| Tritanopia (no blue cones) | #5D4A5E | 0.098 |
| Achromatopsia (no color) | #4E4E4E | 0.136 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #643A8D
#643A8D
oklch(44% 0.135 304.8)
- #455C00
#455C00
oklch(44% 0.11 124.7)
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 #643A8D, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Rebecca Purple #663399 ΔE 0.026
- Dark Slate Blue #483D8B ΔE 0.050
- Blueberry #464196 ΔE 0.055
- Twilight #4E518B ΔE 0.067
- Dusk #4E5481 ΔE 0.080
- Light Eggplant #894585 ΔE 0.082
- Purple #800080 ΔE 0.090
- Grape #7209B7 ΔE 0.094
Use #643A8D 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.