#181C40
Closest named color: Oxford Blue (#1B263B). oklch(24.5% 0.068 275.5), rgb(24, 28, 64).
Aa
White text reads best on this color (16.41:1).
About this color
#181C40 is a very dark, muted blue. In OKLCH its lightness is 24%, its chroma 0.068 and its hue 275°. Its hue sits on the cool side of the wheel. The nearest named color is Oxford Blue (#1B263B), ΔE 0.037 away. White text reads best on it, at 16.41:1.
| Hue family | Blues |
| Lightness | very dark (24%) |
| Chroma | muted (0.068) |
| Temperature | cool |
| Nearest name | Oxford Blue (#1B263B) |
| Black text | 1.27:1 |
| White text | 16.41:1 |
Values
| HEX | #181C40 |
| RGB | rgb(24, 28, 64) |
| HSL | hsl(234, 45%, 17%) |
| OKLCH | oklch(24.5% 0.068 275.5) |
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 #181C40 | 16.41:1 | AAA | Lc -105.7 | Preferred for body text |
| Black text on #181C40 | 1.27:1 | Fails | Lc 0.0 | Not readable |
| #181C40 text on white | 16.41:1 | AAA | Lc 103.2 | Preferred for body text |
| #181C40 text on black | 1.27:1 | 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
#F3F5FD
oklch(97.1% 0.011 274.9)
-
Step 100
100
#E5E9FA
oklch(93.6% 0.023 275.4)
-
Step 200
200
#D0D7F7
oklch(88.4% 0.045 275.7)
-
Step 300
300
#B1BDF5
oklch(80.9% 0.08 275.1)
-
Step 400
400
#8A99F0
oklch(70.7% 0.128 275.2)
-
Step 500
500
#6F7DEB
oklch(63.1% 0.164 275.2)
-
Step 600
600
#5963D9
oklch(55.6% 0.178 275.3)
-
Step 700
700
#4A51BC
oklch(49.1% 0.166 275.6)
-
Step 800
800
#3C4398
oklch(42.6% 0.137 275.4)
-
Step 900
900
#333A79
oklch(37.8% 0.106 275.3)
-
Step 950
950 (this color)
#181C40
oklch(24.5% 0.068 275.5)
#181C40 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) | #0A2141 | 0.022 |
| Deuteranopia (no green cones) | #051E3F | 0.024 |
| Tritanopia (no blue cones) | #05242A | 0.060 |
| Achromatopsia (no color) | #1F1F1F | 0.068 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #181C40
#181C40
oklch(24.5% 0.068 275.5)
- #282000
#282000
oklch(24.6% 0.05 95.4)
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 #181C40, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Oxford Blue #1B263B ΔE 0.037
- Dark #1B2431 ΔE 0.044
- Rich Black #0D1B2A ΔE 0.047
- Navy Blue #001146 ΔE 0.052
- Dark Indigo #1F0954 ΔE 0.057
- Jet #212529 ΔE 0.062
- Space Cadet #2B2D42 ΔE 0.067
- Midnight Purple #280137 ΔE 0.073
Use #181C40 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.