#664D9B
Closest named color: Twilight (#4E518B). oklch(48.3% 0.123 296.3), rgb(102, 77, 155).
Aa
White text reads best on this color (6.77:1).
About this color
#664D9B is a medium-dark, moderately saturated purple. In OKLCH its lightness is 48%, its chroma 0.123 and its hue 296°. Its hue sits between the warm and cool halves of the wheel. The nearest named color is Twilight (#4E518B), ΔE 0.049 away. White text reads best on it, at 6.77:1.
| Hue family | Purples |
| Lightness | medium-dark (48%) |
| Chroma | moderately saturated (0.123) |
| Temperature | in between |
| Nearest name | Twilight (#4E518B) |
| Black text | 3.09:1 |
| White text | 6.77:1 |
Values
| HEX | #664D9B |
| RGB | rgb(102, 77, 155) |
| HSL | hsl(259, 34%, 45%) |
| OKLCH | oklch(48.3% 0.123 296.3) |
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 #664D9B | 6.77:1 | AA | Lc -88.2 | Fine for body text |
| Black text on #664D9B | 3.09:1 | AA large text | Lc 20.9 | Dividers and decoration only |
| #664D9B text on white | 6.77:1 | AA | Lc 83.2 | Fine for body text |
| #664D9B text on black | 3.09:1 | AA large text | Lc -18.8 | 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
#F6F4FA
oklch(97% 0.008 301.4)
-
Step 100
100
#EBE8F4
oklch(93.7% 0.016 297.5)
-
Step 200
200
#DBD5ED
oklch(88.5% 0.033 297.2)
-
Step 300
300
#C4B9E3
oklch(80.9% 0.06 297)
-
Step 400
400
#A694D5
oklch(70.6% 0.095 296.6)
-
Step 500
500
#9179CA
oklch(63.2% 0.121 296.4)
-
Step 600
600
#7B60B7
oklch(55.5% 0.133 296.1)
-
Step 700
700 (this color)
#664D9B
oklch(48.3% 0.123 296.3)
-
Step 800
800
#554180
oklch(42.7% 0.103 296.4)
-
Step 900
900
#463866
oklch(37.8% 0.078 296.5)
-
Step 950
950
#29213C
oklch(27.1% 0.05 296.6)
#664D9B 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) | #315C9E | 0.078 |
| Deuteranopia (no green cones) | #375A99 | 0.072 |
| Tritanopia (no blue cones) | #5A5C6D | 0.097 |
| Achromatopsia (no color) | #5B5B5B | 0.123 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #664D9B
#664D9B
oklch(48.3% 0.123 296.3)
- #5C6600
#5C6600
oklch(48.5% 0.111 116.3)
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 #664D9B, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight #4E518B ΔE 0.049
- Rebecca Purple #663399 ΔE 0.060
- Dusk #4E5481 ΔE 0.063
- Blueberry #464196 ΔE 0.065
- Dusky Blue #475F94 ΔE 0.066
- Iris #6258C4 ΔE 0.067
- Denim Blue #3B5B92 ΔE 0.072
- Dark Slate Blue #483D8B ΔE 0.073
Use #664D9B 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.