#181B4F
Closest named color: Dark Indigo (#1F0954). oklch(25.6% 0.094 275.1), rgb(24, 27, 79).
Aa
White text reads best on this color (16.04:1).
About this color
#181B4F is a dark, moderately saturated blue. In OKLCH its lightness is 26%, its chroma 0.094 and its hue 275°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Indigo (#1F0954), ΔE 0.039 away. White text reads best on it, at 16.04:1.
| Hue family | Blues |
| Lightness | dark (26%) |
| Chroma | moderately saturated (0.094) |
| Temperature | cool |
| Nearest name | Dark Indigo (#1F0954) |
| Black text | 1.30:1 |
| White text | 16.04:1 |
Values
| HEX | #181B4F |
| RGB | rgb(24, 27, 79) |
| HSL | hsl(237, 53%, 20%) |
| OKLCH | oklch(25.6% 0.094 275.1) |
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 #181B4F | 16.04:1 | AAA | Lc -105.3 | Preferred for body text |
| Black text on #181B4F | 1.30:1 | Fails | Lc 0.0 | Not readable |
| #181B4F text on white | 16.04:1 | AAA | Lc 102.7 | Preferred for body text |
| #181B4F text on black | 1.30:1 | 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
#E3E9FF
oklch(93.6% 0.03 273.6)
-
Step 200
200
#CED7FF
oklch(88.5% 0.056 275.2)
-
Step 300
300
#AEBCFF
oklch(80.9% 0.096 274.9)
-
Step 400
400
#8696FF
oklch(70.7% 0.154 275.2)
-
Step 500
500
#6A77FF
oklch(63% 0.2 275)
-
Step 600
600
#5453FF
oklch(55.7% 0.246 275.1)
-
Step 700
700
#4541DF
oklch(49.1% 0.23 274.9)
-
Step 800
800
#3837B4
oklch(42.7% 0.191 275)
-
Step 900
900
#2F328E
oklch(37.6% 0.149 275.2)
-
Step 950
950 (this color)
#181B4F
oklch(25.6% 0.094 275.1)
#181B4F 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) | #002451 | 0.033 |
| Deuteranopia (no green cones) | #001F4E | 0.028 |
| Tritanopia (no blue cones) | #002832 | 0.078 |
| Achromatopsia (no color) | #212121 | 0.094 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #181B4F
#181B4F
oklch(25.6% 0.094 275.1)
- #2B2200
#2B2200
oklch(25.5% 0.052 94.3)
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 #181B4F, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Indigo #1F0954 ΔE 0.039
- Navy Blue #001146 ΔE 0.051
- Oxford Blue #1B263B ΔE 0.055
- Midnight Blue #191970 ΔE 0.059
- Marine #042E60 ΔE 0.060
- Darkblue #030764 ΔE 0.063
- Dark #1B2431 ΔE 0.068
- Night Blue #040348 ΔE 0.072
Use #181B4F 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.