#663788
Closest named color: Rebecca Purple (#663399). oklch(43.4% 0.134 308.6), rgb(102, 55, 136).
Aa
White text reads best on this color (8.51:1).
About this color
#663788 is a dark, moderately saturated purple. In OKLCH its lightness is 43%, its chroma 0.134 and its hue 309°. Its hue sits between the warm and cool halves of the wheel. The nearest named color is Rebecca Purple (#663399), ΔE 0.030 away. White text reads best on it, at 8.51:1.
| Hue family | Purples |
| Lightness | dark (43%) |
| Chroma | moderately saturated (0.134) |
| Temperature | in between |
| Nearest name | Rebecca Purple (#663399) |
| Black text | 2.46:1 |
| White text | 8.51:1 |
Values
| HEX | #663788 |
| RGB | rgb(102, 55, 136) |
| HSL | hsl(275, 42%, 37%) |
| OKLCH | oklch(43.4% 0.134 308.6) |
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 #663788 | 8.51:1 | AAA | Lc -93.5 | Preferred for body text |
| Black text on #663788 | 2.46:1 | Fails | Lc 15.1 | Dividers and decoration only |
| #663788 text on white | 8.51:1 | AAA | Lc 88.9 | Fine for body text |
| #663788 text on black | 2.46:1 | Fails | Lc -13.3 | 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
#EEE6F6
oklch(93.6% 0.023 308.2)
-
Step 200
200
#E1D2F0
oklch(88.5% 0.044 307.9)
-
Step 300
300
#CFB3E8
oklch(80.8% 0.079 308.6)
-
Step 400
400
#B78ADC
oklch(70.7% 0.125 308.7)
-
Step 500
500
#A56AD2
oklch(63% 0.16 308.7)
-
Step 600
600
#904FBF
oklch(55.5% 0.174 308.5)
-
Step 700
700
#7B3FA5
oklch(49.1% 0.162 308.7)
-
Step 800
800 (this color)
#663788
oklch(43.4% 0.134 308.6)
-
Step 900
900
#512F6B
oklch(37.6% 0.104 308.4)
-
Step 950
950
#301C3F
oklch(27% 0.067 309)
#663788 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) | #194B8B | 0.114 |
| Deuteranopia (no green cones) | #2C4D86 | 0.101 |
| Tritanopia (no blue cones) | #61465A | 0.095 |
| Achromatopsia (no color) | #4D4D4D | 0.135 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #663788
#663788
oklch(43.4% 0.134 308.6)
- #3D5C00
#3D5C00
oklch(43.4% 0.115 128.7)
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 #663788, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Rebecca Purple #663399 ΔE 0.030
- Dark Slate Blue #483D8B ΔE 0.055
- Blueberry #464196 ΔE 0.063
- Twilight #4E518B ΔE 0.074
- Light Eggplant #894585 ΔE 0.080
- Purple #800080 ΔE 0.082
- Dusk #4E5481 ΔE 0.085
- Dark Magenta #8B008B ΔE 0.092
Use #663788 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.