#181B4D
Closest named color: Dark Indigo (#1F0954). oklch(25.4% 0.091 275.3), rgb(24, 27, 77).
Aa
White text reads best on this color (16.11:1).
About this color
#181B4D is a dark, moderately saturated blue. In OKLCH its lightness is 25%, its chroma 0.091 and its hue 275°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Indigo (#1F0954), ΔE 0.040 away. White text reads best on it, at 16.11:1.
| Hue family | Blues |
| Lightness | dark (25%) |
| Chroma | moderately saturated (0.091) |
| Temperature | cool |
| Nearest name | Dark Indigo (#1F0954) |
| Black text | 1.30:1 |
| White text | 16.11:1 |
Values
| HEX | #181B4D |
| RGB | rgb(24, 27, 77) |
| HSL | hsl(237, 52%, 20%) |
| OKLCH | oklch(25.4% 0.091 275.3) |
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 #181B4D | 16.11:1 | AAA | Lc -105.4 | Preferred for body text |
| Black text on #181B4D | 1.30:1 | Fails | Lc 0.0 | Not readable |
| #181B4D text on white | 16.11:1 | AAA | Lc 102.8 | Preferred for body text |
| #181B4D 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
#F3F5FF
oklch(97.2% 0.013 277.1)
-
Step 100
100
#E4E9FF
oklch(93.7% 0.03 275.6)
-
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
#6B77FF
oklch(63.1% 0.199 275.3)
-
Step 600
600
#5555FA
oklch(55.6% 0.238 275.4)
-
Step 700
700
#4643DA
oklch(49% 0.222 275.3)
-
Step 800
800
#3939B0
oklch(42.7% 0.183 275.3)
-
Step 900
900
#30338B
oklch(37.6% 0.143 275.6)
-
Step 950
950 (this color)
#181B4D
oklch(25.4% 0.091 275.3)
#181B4D 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) | #00234F | 0.031 |
| Deuteranopia (no green cones) | #001F4C | 0.028 |
| Tritanopia (no blue cones) | #002731 | 0.075 |
| Achromatopsia (no color) | #212121 | 0.091 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #181B4D
#181B4D
oklch(25.4% 0.091 275.3)
- #2A2200
#2A2200
oklch(25.4% 0.052 96)
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 #181B4D, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Indigo #1F0954 ΔE 0.040
- Navy Blue #001146 ΔE 0.050
- Oxford Blue #1B263B ΔE 0.052
- Marine #042E60 ΔE 0.062
- Midnight Blue #191970 ΔE 0.063
- Dark #1B2431 ΔE 0.065
- Darkblue #030764 ΔE 0.065
- Rich Black #0D1B2A ΔE 0.070
Use #181B4D 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.