#151B4A
Closest named color: Dark Indigo (#1F0954). oklch(24.9% 0.087 272.9), rgb(21, 27, 74).
Aa
White text reads best on this color (16.31:1).
About this color
#151B4A is a very dark, moderately saturated blue. In OKLCH its lightness is 25%, its chroma 0.087 and its hue 273°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Indigo (#1F0954), ΔE 0.043 away. White text reads best on it, at 16.31:1.
| Hue family | Blues |
| Lightness | very dark (25%) |
| Chroma | moderately saturated (0.087) |
| Temperature | cool |
| Nearest name | Dark Indigo (#1F0954) |
| Black text | 1.28:1 |
| White text | 16.31:1 |
Values
| HEX | #151B4A |
| RGB | rgb(21, 27, 74) |
| HSL | hsl(233, 56%, 19%) |
| OKLCH | oklch(24.9% 0.087 272.9) |
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 #151B4A | 16.31:1 | AAA | Lc -105.6 | Preferred for body text |
| Black text on #151B4A | 1.28:1 | Fails | Lc 0.0 | Not readable |
| #151B4A text on white | 16.31:1 | AAA | Lc 103.0 | Preferred for body text |
| #151B4A text on black | 1.28:1 | 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
#F2F5FF
oklch(97.1% 0.014 272.7)
-
Step 100
100
#E3E9FE
oklch(93.6% 0.029 273.1)
-
Step 200
200
#CCD7FF
oklch(88.4% 0.057 273.1)
-
Step 300
300
#ACBDFF
oklch(80.9% 0.095 273)
-
Step 400
400
#8298FF
oklch(70.8% 0.152 272.8)
-
Step 500
500
#6579FF
oklch(63.1% 0.198 273)
-
Step 600
600
#4E5AF5
oklch(55.5% 0.228 272.9)
-
Step 700
700
#4048D6
oklch(49% 0.213 273)
-
Step 800
800
#343DAD
oklch(42.7% 0.176 272.8)
-
Step 900
900
#2C3689
oklch(37.7% 0.137 272.7)
-
Step 950
950 (this color)
#151B4A
oklch(24.9% 0.087 272.9)
#151B4A 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) | #00224C | 0.027 |
| Deuteranopia (no green cones) | #001E49 | 0.024 |
| Tritanopia (no blue cones) | #00262F | 0.072 |
| Achromatopsia (no color) | #202020 | 0.087 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #151B4A
#151B4A
oklch(24.9% 0.087 272.9)
- #2A2000
#2A2000
oklch(24.8% 0.051 91.8)
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 #151B4A, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Indigo #1F0954 ΔE 0.043
- Navy Blue #001146 ΔE 0.045
- Oxford Blue #1B263B ΔE 0.050
- Dark #1B2431 ΔE 0.061
- Rich Black #0D1B2A ΔE 0.064
- Marine #042E60 ΔE 0.065
- Darkblue #030764 ΔE 0.066
- Night Blue #040348 ΔE 0.068
Use #151B4A 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.