#181F33
Closest named color: Dark (#1B2431). oklch(24.3% 0.04 268.6), rgb(24, 31, 51).
Aa
White text reads best on this color (16.37:1).
About this color
#181F33 is a very dark, muted blue. In OKLCH its lightness is 24%, its chroma 0.040 and its hue 269°. Its hue sits on the cool side of the wheel. The nearest named color is Dark (#1B2431), ΔE 0.020 away. White text reads best on it, at 16.37:1.
| Hue family | Blues |
| Lightness | very dark (24%) |
| Chroma | muted (0.040) |
| Temperature | cool |
| Nearest name | Dark (#1B2431) |
| Black text | 1.28:1 |
| White text | 16.37:1 |
Values
| HEX | #181F33 |
| RGB | rgb(24, 31, 51) |
| HSL | hsl(224, 36%, 15%) |
| OKLCH | oklch(24.3% 0.04 268.6) |
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 #181F33 | 16.37:1 | AAA | Lc -105.8 | Preferred for body text |
| Black text on #181F33 | 1.28:1 | Fails | Lc 0.0 | Not readable |
| #181F33 text on white | 16.37:1 | AAA | Lc 103.3 | Preferred for body text |
| #181F33 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
#F4F5FA
oklch(97.1% 0.007 277.2)
-
Step 100
100
#E6EAF3
oklch(93.7% 0.013 266.7)
-
Step 200
200
#D2D9EB
oklch(88.5% 0.026 268.8)
-
Step 300
300
#B4C0E0
oklch(80.9% 0.047 269.1)
-
Step 400
400
#8D9FD0
oklch(70.7% 0.075 268.8)
-
Step 500
500
#7187C4
oklch(63.1% 0.096 268.4)
-
Step 600
600
#5A70B1
oklch(55.7% 0.105 268.7)
-
Step 700
700
#4A5D98
oklch(49.1% 0.098 269.1)
-
Step 800
800
#3D4C7B
oklch(42.6% 0.081 269.4)
-
Step 900
900
#344063
oklch(37.8% 0.062 268.9)
-
Step 950
950 (this color)
#181F33
oklch(24.3% 0.04 268.6)
#181F33 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) | #182134 | 0.007 |
| Deuteranopia (no green cones) | #151F33 | 0.005 |
| Tritanopia (no blue cones) | #0E2326 | 0.036 |
| Achromatopsia (no color) | #202020 | 0.040 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #181F33
#181F33
oklch(24.3% 0.04 268.6)
- #281F07
#281F07
oklch(24.4% 0.04 88.6)
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 #181F33, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark #1B2431 ΔE 0.020
- Oxford Blue #1B263B ΔE 0.027
- Rich Black #0D1B2A ΔE 0.028
- Jet #212529 ΔE 0.036
- Space Cadet #2B2D42 ΔE 0.062
- Navy Blue #001146 ΔE 0.071
- Gunmetal #293241 ΔE 0.073
- Rich Navy #001219 ΔE 0.079
Use #181F33 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.