#66437B
Closest named color: Twilight (#4E518B). oklch(44.6% 0.097 311.8), rgb(102, 67, 123).
Aa
White text reads best on this color (7.91:1).
About this color
#66437B is a dark, moderately saturated purple. In OKLCH its lightness is 45%, its chroma 0.097 and its hue 312°. Its hue sits between the warm and cool halves of the wheel. The nearest named color is Twilight (#4E518B), ΔE 0.054 away. White text reads best on it, at 7.91:1.
| Hue family | Purples |
| Lightness | dark (45%) |
| Chroma | moderately saturated (0.097) |
| Temperature | in between |
| Nearest name | Twilight (#4E518B) |
| Black text | 2.65:1 |
| White text | 7.91:1 |
Values
| HEX | #66437B |
| RGB | rgb(102, 67, 123) |
| HSL | hsl(278, 29%, 37%) |
| OKLCH | oklch(44.6% 0.097 311.8) |
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 #66437B | 7.91:1 | AAA | Lc -92.0 | Preferred for body text |
| Black text on #66437B | 2.65:1 | Fails | Lc 16.7 | Dividers and decoration only |
| #66437B text on white | 7.91:1 | AAA | Lc 87.3 | Fine for body text |
| #66437B text on black | 2.65:1 | Fails | Lc -14.8 | 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
#F7F4F9
oklch(97.1% 0.007 312.3)
-
Step 100
100
#EDE7F2
oklch(93.6% 0.016 310.1)
-
Step 200
200
#E0D4E9
oklch(88.6% 0.031 311)
-
Step 300
300
#CDB7DC
oklch(81% 0.056 311.6)
-
Step 400
400
#B390CA
oklch(70.6% 0.091 311.5)
-
Step 500
500
#A174BC
oklch(63.1% 0.116 312.1)
-
Step 600
600
#8C5BA8
oklch(55.6% 0.126 312.2)
-
Step 700
700
#774B90
oklch(49.2% 0.116 312.2)
-
Step 800
800 (this color)
#66437B
oklch(44.6% 0.097 311.8)
-
Step 900
900
#4F355F
oklch(37.8% 0.076 311.6)
-
Step 950
950
#2E1F37
oklch(26.9% 0.048 312.1)
#66437B 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) | #374F7D | 0.078 |
| Deuteranopia (no green cones) | #405279 | 0.071 |
| Tritanopia (no blue cones) | #644B59 | 0.067 |
| Achromatopsia (no color) | #515151 | 0.098 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #66437B
#66437B
oklch(44.6% 0.097 311.8)
- #405F21
#405F21
oklch(44.7% 0.097 131.7)
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 #66437B, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight #4E518B ΔE 0.054
- Dusk #4E5481 ΔE 0.057
- Dusty Grape #545775 ΔE 0.064
- Dark Slate Blue #483D8B ΔE 0.065
- Rebecca Purple #663399 ΔE 0.066
- Light Eggplant #894585 ΔE 0.069
- Blueberry #464196 ΔE 0.073
- Brownish Purple #76424E ΔE 0.080
Use #66437B 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.