#183A54
Closest named color: Dark Blue Grey (#1F3B4D). oklch(33.6% 0.061 244.2), rgb(24, 58, 84).
Aa
White text reads best on this color (11.85:1).
About this color
#183A54 is a dark, muted blue. In OKLCH its lightness is 34%, its chroma 0.061 and its hue 244°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Blue Grey (#1F3B4D), ΔE 0.015 away. White text reads best on it, at 11.85:1.
| Hue family | Blues |
| Lightness | dark (34%) |
| Chroma | muted (0.061) |
| Temperature | cool |
| Nearest name | Dark Blue Grey (#1F3B4D) |
| Black text | 1.77:1 |
| White text | 11.85:1 |
Values
| HEX | #183A54 |
| RGB | rgb(24, 58, 84) |
| HSL | hsl(206, 56%, 21%) |
| OKLCH | oklch(33.6% 0.061 244.2) |
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 #183A54 | 11.85:1 | AAA | Lc -100.6 | Preferred for body text |
| Black text on #183A54 | 1.77:1 | Fails | Lc 0.0 | Not readable |
| #183A54 text on white | 11.85:1 | AAA | Lc 97.0 | Preferred for body text |
| #183A54 text on black | 1.77:1 | 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 900.
-
Step 50
50
#F2F6F9
oklch(97.1% 0.006 239.8)
-
Step 100
100
#E3EBF2
oklch(93.6% 0.013 244.3)
-
Step 200
200
#CCDBE9
oklch(88.4% 0.025 246.2)
-
Step 300
300
#A9C5DC
oklch(81% 0.045 243.1)
-
Step 400
400
#79A6CB
oklch(70.7% 0.073 243.9)
-
Step 500
500
#558FBE
oklch(63% 0.094 244.5)
-
Step 600
600
#3979AA
oklch(55.6% 0.101 244.2)
-
Step 700
700
#2A6692
oklch(49.2% 0.094 243.7)
-
Step 800
800
#255376
oklch(42.7% 0.077 244.1)
-
Step 900
900 (this color)
#183A54
oklch(33.6% 0.061 244.2)
-
Step 950
950
#152838
oklch(26.9% 0.039 245.4)
#183A54 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) | #2E3B55 | 0.027 |
| Deuteranopia (no green cones) | #263554 | 0.021 |
| Tritanopia (no blue cones) | #004043 | 0.044 |
| Achromatopsia (no color) | #373737 | 0.061 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #183A54
#183A54
oklch(33.6% 0.061 244.2)
- #4D3011
#4D3011
oklch(33.8% 0.061 64.6)
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 #183A54, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Blue Grey #1F3B4D ΔE 0.015
- Prussian Blue #1D3557 ΔE 0.019
- Midnight Green #073B4C ΔE 0.020
- Gunmetal #293241 ΔE 0.039
- Marine Blue #01386A ΔE 0.043
- Charcoal #264653 ΔE 0.045
- Dark Grey Blue #29465B ΔE 0.046
- Onyx #343A40 ΔE 0.048
Use #183A54 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.