#66399D
Closest named color: Rebecca Purple (#663399). oklch(45.2% 0.156 301), rgb(102, 57, 157).
Aa
White text reads best on this color (7.96:1).
About this color
#66399D is a medium-dark, vivid purple. In OKLCH its lightness is 45%, its chroma 0.156 and its hue 301°. Its hue sits between the warm and cool halves of the wheel. The nearest named color is Rebecca Purple (#663399), ΔE 0.014 away. White text reads best on it, at 7.96:1.
| Hue family | Purples |
| Lightness | medium-dark (45%) |
| Chroma | vivid (0.156) |
| Temperature | in between |
| Nearest name | Rebecca Purple (#663399) |
| Black text | 2.63:1 |
| White text | 7.96:1 |
Values
| HEX | #66399D |
| RGB | rgb(102, 57, 157) |
| HSL | hsl(267, 47%, 42%) |
| OKLCH | oklch(45.2% 0.156 301) |
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 #66399D | 7.96:1 | AAA | Lc -91.9 | Preferred for body text |
| Black text on #66399D | 2.63:1 | Fails | Lc 16.9 | Dividers and decoration only |
| #66399D text on white | 7.96:1 | AAA | Lc 87.1 | Fine for body text |
| #66399D text on black | 2.63:1 | Fails | Lc -15.0 | 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
#F7F4FD
oklch(97.2% 0.012 301.3)
-
Step 100
100
#EDE6F9
oklch(93.6% 0.026 302.6)
-
Step 200
200
#DED2F6
oklch(88.5% 0.051 300.6)
-
Step 300
300
#CAB3F3
oklch(80.8% 0.092 300.8)
-
Step 400
400
#B189ED
oklch(70.8% 0.147 301.2)
-
Step 500
500
#9E67E7
oklch(63% 0.188 301)
-
Step 600
600
#8A4AD5
oklch(55.6% 0.204 301.1)
-
Step 700
700
#753AB8
oklch(49% 0.189 301.1)
-
Step 800
800 (this color)
#66399D
oklch(45.2% 0.156 301)
-
Step 900
900
#4E2D77
oklch(37.8% 0.122 301.3)
-
Step 950
950
#2D1B46
oklch(27% 0.078 300.6)
#66399D 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) | #0050A0 | 0.119 |
| Deuteranopia (no green cones) | #14509B | 0.113 |
| Tritanopia (no blue cones) | #5A4F65 | 0.119 |
| Achromatopsia (no color) | #515151 | 0.157 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #66399D
#66399D
oklch(45.2% 0.156 301)
- #4D5E00
#4D5E00
oklch(45.1% 0.108 121.1)
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 #66399D, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Rebecca Purple #663399 ΔE 0.014
- Blueberry #464196 ΔE 0.058
- Dark Slate Blue #483D8B ΔE 0.061
- Bluey Purple #6241C7 ΔE 0.069
- Grape #7209B7 ΔE 0.073
- Blue With A Hint Of Purple #533CC6 ΔE 0.075
- Twilight #4E518B ΔE 0.078
- Chrysanthemum #560BAD ΔE 0.080
Use #66399D 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.