#151B39
Closest named color: Rich Black (#0D1B2A). oklch(23.4% 0.058 272.7), rgb(21, 27, 57).
Aa
White text reads best on this color (16.83:1).
About this color
#151B39 is a very dark, muted blue. In OKLCH its lightness is 23%, its chroma 0.058 and its hue 273°. Its hue sits on the cool side of the wheel. The nearest named color is Rich Black (#0D1B2A), ΔE 0.033 away. White text reads best on it, at 16.83:1.
| Hue family | Blues |
| Lightness | very dark (23%) |
| Chroma | muted (0.058) |
| Temperature | cool |
| Nearest name | Rich Black (#0D1B2A) |
| Black text | 1.24:1 |
| White text | 16.83:1 |
Values
| HEX | #151B39 |
| RGB | rgb(21, 27, 57) |
| HSL | hsl(230, 46%, 15%) |
| OKLCH | oklch(23.4% 0.058 272.7) |
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 #151B39 | 16.83:1 | AAA | Lc -106.1 | Preferred for body text |
| Black text on #151B39 | 1.24:1 | Fails | Lc 0.0 | Not readable |
| #151B39 text on white | 16.83:1 | AAA | Lc 103.7 | Preferred for body text |
| #151B39 text on black | 1.24:1 | 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
#D0D8F3
oklch(88.5% 0.038 272.5)
-
Step 300
300
#B1BEEE
oklch(80.8% 0.07 272.9)
-
Step 400
400
#899CE5
oklch(70.7% 0.109 272.2)
-
Step 500
500
#6D81DE
oklch(63% 0.141 272.6)
-
Step 600
600
#5769CC
oklch(55.7% 0.153 272.7)
-
Step 700
700
#4757B0
oklch(49.1% 0.142 272.5)
-
Step 800
800
#3A478F
oklch(42.6% 0.119 272.7)
-
Step 900
900
#323C72
oklch(37.6% 0.093 273.3)
-
Step 950
950 (this color)
#151B39
oklch(23.4% 0.058 272.7)
#151B39 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) | #0E1F3A | 0.015 |
| Deuteranopia (no green cones) | #091C38 | 0.016 |
| Tritanopia (no blue cones) | #042227 | 0.052 |
| Achromatopsia (no color) | #1D1D1D | 0.058 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #151B39
#151B39
oklch(23.4% 0.058 272.7)
- #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 #151B39, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Rich Black #0D1B2A ΔE 0.033
- Oxford Blue #1B263B ΔE 0.039
- Dark #1B2431 ΔE 0.040
- Navy Blue #001146 ΔE 0.052
- Jet #212529 ΔE 0.057
- Dark Indigo #1F0954 ΔE 0.067
- Midnight Purple #280137 ΔE 0.073
- Space Cadet #2B2D42 ΔE 0.074
Use #151B39 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.