#151B3B
Closest named color: Rich Black (#0D1B2A). oklch(23.6% 0.062 272.8), rgb(21, 27, 59).
Aa
White text reads best on this color (16.77:1).
About this color
#151B3B is a very dark, muted blue. In OKLCH its lightness is 24%, its chroma 0.062 and its hue 273°. Its hue sits on the cool side of the wheel. The nearest named color is Rich Black (#0D1B2A), ΔE 0.036 away. White text reads best on it, at 16.77:1.
| Hue family | Blues |
| Lightness | very dark (24%) |
| Chroma | muted (0.062) |
| Temperature | cool |
| Nearest name | Rich Black (#0D1B2A) |
| Black text | 1.25:1 |
| White text | 16.77:1 |
Values
| HEX | #151B3B |
| RGB | rgb(21, 27, 59) |
| HSL | hsl(231, 48%, 16%) |
| OKLCH | oklch(23.6% 0.062 272.8) |
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 #151B3B | 16.77:1 | AAA | Lc -106.0 | Preferred for body text |
| Black text on #151B3B | 1.25:1 | Fails | Lc 0.0 | Not readable |
| #151B3B text on white | 16.77:1 | AAA | Lc 103.6 | Preferred for body text |
| #151B3B text on black | 1.25:1 | 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
#F3F5FC
oklch(97.1% 0.01 273.4)
-
Step 100
100
#E5E9F8
oklch(93.5% 0.021 274)
-
Step 200
200
#D0D8F5
oklch(88.5% 0.041 273.3)
-
Step 300
300
#B0BEF1
oklch(80.8% 0.074 272.7)
-
Step 400
400
#889BE9
oklch(70.6% 0.116 272.7)
-
Step 500
500
#6C80E3
oklch(63% 0.15 272.8)
-
Step 600
600
#5667D1
oklch(55.6% 0.163 273.1)
-
Step 700
700
#4655B5
oklch(49% 0.152 272.8)
-
Step 800
800
#3A4692
oklch(42.6% 0.125 273.2)
-
Step 900
900
#313C75
oklch(37.8% 0.098 272.7)
-
Step 950
950 (this color)
#151B3B
oklch(23.6% 0.062 272.8)
#151B3B 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) | #0C1F3C | 0.016 |
| Deuteranopia (no green cones) | #071C3A | 0.018 |
| Tritanopia (no blue cones) | #022228 | 0.054 |
| Achromatopsia (no color) | #1D1D1D | 0.062 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #151B3B
#151B3B
oklch(23.6% 0.062 272.8)
- #261D00
#261D00
oklch(23.5% 0.048 92.4)
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 #151B3B, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Rich Black #0D1B2A ΔE 0.036
- Oxford Blue #1B263B ΔE 0.039
- Dark #1B2431 ΔE 0.042
- Navy Blue #001146 ΔE 0.050
- Jet #212529 ΔE 0.059
- Dark Indigo #1F0954 ΔE 0.063
- Midnight Purple #280137 ΔE 0.073
- Space Cadet #2B2D42 ΔE 0.073
Use #151B3B 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.