#183755
Closest named color: Prussian Blue (#1D3557). oklch(32.9% 0.065 249.8), rgb(24, 55, 85).
Aa
White text reads best on this color (12.23:1).
About this color
#183755 is a dark, muted blue. In OKLCH its lightness is 33%, its chroma 0.065 and its hue 250°. Its hue sits on the cool side of the wheel. The nearest named color is Prussian Blue (#1D3557), ΔE 0.009 away. White text reads best on it, at 12.23:1.
| Hue family | Blues |
| Lightness | dark (33%) |
| Chroma | muted (0.065) |
| Temperature | cool |
| Nearest name | Prussian Blue (#1D3557) |
| Black text | 1.71:1 |
| White text | 12.23:1 |
Values
| HEX | #183755 |
| RGB | rgb(24, 55, 85) |
| HSL | hsl(210, 56%, 21%) |
| OKLCH | oklch(32.9% 0.065 249.8) |
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 #183755 | 12.23:1 | AAA | Lc -101.2 | Preferred for body text |
| Black text on #183755 | 1.71:1 | Fails | Lc 0.0 | Not readable |
| #183755 text on white | 12.23:1 | AAA | Lc 97.7 | Preferred for body text |
| #183755 text on black | 1.71:1 | 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
#F2F6FA
oklch(97.1% 0.007 247.9)
-
Step 100
100
#E3EBF3
oklch(93.6% 0.014 248)
-
Step 200
200
#CCDBEB
oklch(88.5% 0.027 249.9)
-
Step 300
300
#A9C4DF
oklch(80.9% 0.048 248.4)
-
Step 400
400
#7BA5D0
oklch(70.8% 0.078 249.6)
-
Step 500
500
#588EC3
oklch(63.1% 0.099 249.2)
-
Step 600
600
#3C77B0
oklch(55.6% 0.108 249.7)
-
Step 700
700
#2E6497
oklch(49.1% 0.1 249.4)
-
Step 800
800
#27527B
oklch(42.8% 0.084 249.4)
-
Step 900
900 (this color)
#183755
oklch(32.9% 0.065 249.8)
-
Step 950
950
#16283A
oklch(27.1% 0.041 249.6)
#183755 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) | #2A3856 | 0.023 |
| Deuteranopia (no green cones) | #213354 | 0.015 |
| Tritanopia (no blue cones) | #003E42 | 0.050 |
| Achromatopsia (no color) | #353535 | 0.065 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #183755
#183755
oklch(32.9% 0.065 249.8)
- #4A2E08
#4A2E08
oklch(32.8% 0.065 69.2)
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 #183755, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Prussian Blue #1D3557 ΔE 0.009
- Dark Blue Grey #1F3B4D ΔE 0.023
- Midnight Green #073B4C ΔE 0.026
- Marine Blue #01386A ΔE 0.038
- Gunmetal #293241 ΔE 0.039
- Marine #042E60 ΔE 0.042
- Space Cadet #2B2D42 ΔE 0.044
- Onyx #343A40 ΔE 0.054
Use #183755 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.