#66539B
Closest named color: Twilight (#4E518B). oklch(49.5% 0.113 294), rgb(102, 83, 155).
Aa
White text reads best on this color (6.41:1).
About this color
#66539B is a medium-dark, moderately saturated purple. In OKLCH its lightness is 49%, its chroma 0.113 and its hue 294°. Its hue sits between the warm and cool halves of the wheel. The nearest named color is Twilight (#4E518B), ΔE 0.047 away. White text reads best on it, at 6.41:1.
| Hue family | Purples |
| Lightness | medium-dark (49%) |
| Chroma | moderately saturated (0.113) |
| Temperature | in between |
| Nearest name | Twilight (#4E518B) |
| Black text | 3.27:1 |
| White text | 6.41:1 |
Values
| HEX | #66539B |
| RGB | rgb(102, 83, 155) |
| HSL | hsl(256, 30%, 47%) |
| OKLCH | oklch(49.5% 0.113 294) |
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 #66539B | 6.41:1 | AA | Lc -86.8 | Fine for body text |
| Black text on #66539B | 3.27:1 | AA large text | Lc 22.3 | Dividers and decoration only |
| #66539B text on white | 6.41:1 | AA | Lc 81.7 | Fine for body text |
| #66539B text on black | 3.27:1 | AA large text | Lc -20.2 | Dividers and decoration only |
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 700.
-
Step 50
50
#F5F5FA
oklch(97.2% 0.007 286.3)
-
Step 100
100
#EAE8F4
oklch(93.6% 0.016 293.7)
-
Step 200
200
#DAD6EC
oklch(88.6% 0.03 294.1)
-
Step 300
300
#C2BAE1
oklch(80.8% 0.055 294.5)
-
Step 400
400
#A396D2
oklch(70.6% 0.087 294)
-
Step 500
500
#8D7BC6
oklch(63% 0.112 294)
-
Step 600
600
#7863B3
oklch(55.6% 0.122 294.2)
-
Step 700
700 (this color)
#66539B
oklch(49.5% 0.113 294)
-
Step 800
800
#52437D
oklch(42.6% 0.095 293.9)
-
Step 900
900
#443964
oklch(37.6% 0.073 294.4)
-
Step 950
950
#28223B
oklch(27.1% 0.046 294.1)
#66539B 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) | #3B609E | 0.065 |
| Deuteranopia (no green cones) | #3E5E99 | 0.061 |
| Tritanopia (no blue cones) | #5A616F | 0.093 |
| Achromatopsia (no color) | #5F5F5F | 0.113 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #66539B
#66539B
oklch(49.5% 0.113 294)
- #616800
#616800
oklch(49.4% 0.111 114.3)
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 #66539B, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight #4E518B ΔE 0.047
- Dusky Blue #475F94 ΔE 0.056
- Dusk #4E5481 ΔE 0.058
- Muted Purple #805B87 ΔE 0.064
- Iris #6258C4 ΔE 0.065
- Denim Blue #3B5B92 ΔE 0.066
- Dusty Purple #825F87 ΔE 0.072
- Dusty Grape #545775 ΔE 0.073
Use #66539B 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.