#551B8A
Closest named color: Indigo (#4B0082). oklch(37.8% 0.17 302.4), rgb(85, 27, 138).
Aa
White text reads best on this color (10.99:1).
About this color
#551B8A is a dark, vivid purple. In OKLCH its lightness is 38%, its chroma 0.170 and its hue 302°. Its hue sits between the warm and cool halves of the wheel. The nearest named color is Indigo (#4B0082), ΔE 0.041 away. White text reads best on it, at 10.99:1.
| Hue family | Purples |
| Lightness | dark (38%) |
| Chroma | vivid (0.170) |
| Temperature | in between |
| Nearest name | Indigo (#4B0082) |
| Black text | 1.91:1 |
| White text | 10.99:1 |
Values
| HEX | #551B8A |
| RGB | rgb(85, 27, 138) |
| HSL | hsl(271, 67%, 32%) |
| OKLCH | oklch(37.8% 0.17 302.4) |
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 #551B8A | 10.99:1 | AAA | Lc -98.4 | Preferred for body text |
| Black text on #551B8A | 1.91:1 | Fails | Lc 9.5 | Not readable |
| #551B8A text on white | 10.99:1 | AAA | Lc 94.4 | Preferred for body text |
| #551B8A text on black | 1.91:1 | Fails | Lc -8.2 | 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 900.
-
Step 50
50
#F7F3FF
oklch(97.1% 0.016 301.2)
-
Step 100
100
#EEE5FF
oklch(93.7% 0.036 301.4)
-
Step 200
200
#E1CFFF
oklch(88.5% 0.068 302.1)
-
Step 300
300
#CFAEFF
oklch(80.8% 0.117 302.6)
-
Step 400
400
#B87FFF
oklch(70.8% 0.186 302.5)
-
Step 500
500
#A854FF
oklch(63.1% 0.242 302.4)
-
Step 600
600
#9717F7
oklch(55.6% 0.283 302.4)
-
Step 700
700
#8000D5
oklch(49% 0.258 302.3)
-
Step 800
800
#690CAE
oklch(42.8% 0.218 302.5)
-
Step 900
900 (this color)
#551B8A
oklch(37.8% 0.17 302.4)
-
Step 950
950
#311351
oklch(27.1% 0.107 301.7)
#551B8A 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) | #003B8D | 0.118 |
| Deuteranopia (no green cones) | #003C88 | 0.120 |
| Tritanopia (no blue cones) | #4A3952 | 0.124 |
| Achromatopsia (no color) | #3C3C3C | 0.171 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #551B8A
#551B8A
oklch(37.8% 0.17 302.4)
- #3A4900
#3A4900
oklch(37.9% 0.092 122)
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 #551B8A, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Indigo #4B0082 ΔE 0.041
- Chrysanthemum #560BAD ΔE 0.058
- Imperial Purple #480CA8 ΔE 0.061
- Rebecca Purple #663399 ΔE 0.063
- Royal Purple #4B006E ΔE 0.063
- Dark Slate Blue #483D8B ΔE 0.071
- Blueberry #464196 ΔE 0.081
- Indigo Blue #3A18B1 ΔE 0.088
Use #551B8A 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.