#183B7D
Closest named color: Twilight Blue (#0A437A). oklch(36.8% 0.119 261.6), rgb(24, 59, 125).
Aa
White text reads best on this color (10.71:1).
About this color
#183B7D is a dark, moderately saturated blue. In OKLCH its lightness is 37%, its chroma 0.119 and its hue 262°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.024 away. White text reads best on it, at 10.71:1.
| Hue family | Blues |
| Lightness | dark (37%) |
| Chroma | moderately saturated (0.119) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 1.96:1 |
| White text | 10.71:1 |
Values
| HEX | #183B7D |
| RGB | rgb(24, 59, 125) |
| HSL | hsl(219, 68%, 29%) |
| OKLCH | oklch(36.8% 0.119 261.6) |
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 #183B7D | 10.71:1 | AAA | Lc -98.4 | Preferred for body text |
| Black text on #183B7D | 1.96:1 | Fails | Lc 9.5 | Not readable |
| #183B7D text on white | 10.71:1 | AAA | Lc 94.4 | Preferred for body text |
| #183B7D text on black | 1.96:1 | Fails | Lc -8.2 | 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
#F1F6FE
oklch(97.2% 0.012 259.8)
-
Step 100
100
#E0EAFC
oklch(93.5% 0.027 262.3)
-
Step 200
200
#C7DAFB
oklch(88.5% 0.05 261.5)
-
Step 300
300
#A1C1FB
oklch(80.8% 0.09 262.1)
-
Step 400
400
#6D9FF9
oklch(70.7% 0.143 261.4)
-
Step 500
500
#4784F6
oklch(63.2% 0.182 261.6)
-
Step 600
600
#296AE5
oklch(55.6% 0.198 261.6)
-
Step 700
700
#1C57C7
oklch(49% 0.185 261.7)
-
Step 800
800
#1948A1
oklch(42.7% 0.153 261.6)
-
Step 900
900 (this color)
#183B7D
oklch(36.8% 0.119 261.6)
-
Step 950
950
#10254B
oklch(27.1% 0.076 261.2)
#183B7D 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) | #11437F | 0.022 |
| Deuteranopia (no green cones) | #003A7C | 0.015 |
| Tritanopia (no blue cones) | #004B56 | 0.093 |
| Achromatopsia (no color) | #3E3E3E | 0.120 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #183B7D
#183B7D
oklch(36.8% 0.119 261.6)
- #533A00
#533A00
oklch(36.7% 0.076 81.4)
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 #183B7D, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.024
- Marine Blue #01386A ΔE 0.038
- Cobalt #1E488F ΔE 0.047
- Light Navy #155084 ΔE 0.061
- Marine #042E60 ΔE 0.065
- Prussian Blue #1D3557 ΔE 0.066
- Dark Slate Blue #483D8B ΔE 0.070
- Deep Sea Blue #015482 ΔE 0.072
Use #183B7D 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.