#331D6B
Closest named color: Midnight Blue (#191970). oklch(31.2% 0.128 289.9), rgb(51, 29, 107).
Aa
White text reads best on this color (13.73:1).
About this color
#331D6B is a dark, moderately saturated purple. In OKLCH its lightness is 31%, its chroma 0.128 and its hue 290°. Its hue sits on the cool side of the wheel. The nearest named color is Midnight Blue (#191970), ΔE 0.049 away. White text reads best on it, at 13.73:1.
| Hue family | Purples |
| Lightness | dark (31%) |
| Chroma | moderately saturated (0.128) |
| Temperature | cool |
| Nearest name | Midnight Blue (#191970) |
| Black text | 1.52:1 |
| White text | 13.73:1 |
Values
| HEX | #331D6B |
| RGB | rgb(51, 29, 107) |
| HSL | hsl(257, 57%, 27%) |
| OKLCH | oklch(31.2% 0.128 289.9) |
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 #331D6B | 13.73:1 | AAA | Lc -103.0 | Preferred for body text |
| Black text on #331D6B | 1.52:1 | Fails | Lc 0.0 | Not readable |
| #331D6B text on white | 13.73:1 | AAA | Lc 99.8 | Preferred for body text |
| #331D6B text on black | 1.52:1 | Fails | Lc 0.0 | 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 950.
-
Step 50
50
#F5F4FF
oklch(97.1% 0.015 290.3)
-
Step 100
100
#E9E7FF
oklch(93.7% 0.032 289.6)
-
Step 200
200
#D8D3FF
oklch(88.5% 0.06 290.3)
-
Step 300
300
#BFB5FF
oklch(80.8% 0.104 290.1)
-
Step 400
400
#A08BFF
oklch(70.6% 0.166 289.8)
-
Step 500
500
#8C68FF
oklch(63.1% 0.214 289.8)
-
Step 600
600
#7B3AFF
oklch(55.6% 0.265 289.8)
-
Step 700
700
#6B00EE
oklch(49% 0.278 289.7)
-
Step 800
800
#5800C6
oklch(42.7% 0.242 289.8)
-
Step 900
900
#480FA1
oklch(37.6% 0.201 289.9)
-
Step 950
950 (this color)
#331D6B
oklch(31.2% 0.128 289.9)
#331D6B 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) | #002F6D | 0.069 |
| Deuteranopia (no green cones) | #002B69 | 0.067 |
| Tritanopia (no blue cones) | #203141 | 0.103 |
| Achromatopsia (no color) | #2D2D2D | 0.128 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #331D6B
#331D6B
oklch(31.2% 0.128 289.9)
- #333300
#333300
oklch(31.1% 0.068 109.8)
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 #331D6B, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Midnight Blue #191970 ΔE 0.049
- Royal Purple #4B006E ΔE 0.061
- Indigo #4B0082 ΔE 0.066
- Marine #042E60 ΔE 0.071
- Dark Indigo #1F0954 ΔE 0.074
- Prussian Blue #1D3557 ΔE 0.081
- Marine Blue #01386A ΔE 0.083
- Plum Purple #4E0550 ΔE 0.084
Use #331D6B 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.