#18366B
Closest named color: Marine Blue (#01386A). oklch(34.2% 0.099 260.8), rgb(24, 54, 107).
Aa
White text reads best on this color (11.80:1).
About this color
#18366B is a dark, moderately saturated blue. In OKLCH its lightness is 34%, its chroma 0.099 and its hue 261°. Its hue sits on the cool side of the wheel. The nearest named color is Marine Blue (#01386A), ΔE 0.015 away. White text reads best on it, at 11.80:1.
| Hue family | Blues |
| Lightness | dark (34%) |
| Chroma | moderately saturated (0.099) |
| Temperature | cool |
| Nearest name | Marine Blue (#01386A) |
| Black text | 1.77:1 |
| White text | 11.80:1 |
Values
| HEX | #18366B |
| RGB | rgb(24, 54, 107) |
| HSL | hsl(218, 63%, 26%) |
| OKLCH | oklch(34.2% 0.099 260.8) |
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 #18366B | 11.80:1 | AAA | Lc -100.4 | Preferred for body text |
| Black text on #18366B | 1.77:1 | Fails | Lc 0.0 | Not readable |
| #18366B text on white | 11.80:1 | AAA | Lc 96.8 | Preferred for body text |
| #18366B 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
#F2F6FC
oklch(97.2% 0.009 258.3)
-
Step 100
100
#E2EAF9
oklch(93.5% 0.022 263.2)
-
Step 200
200
#CADAF5
oklch(88.5% 0.041 260.9)
-
Step 300
300
#A6C2F1
oklch(81% 0.073 260.7)
-
Step 400
400
#75A0EB
oklch(70.6% 0.12 261)
-
Step 500
500
#5287E4
oklch(63.1% 0.151 260.8)
-
Step 600
600
#366ED2
oklch(55.5% 0.165 260.9)
-
Step 700
700
#295CB6
oklch(49.1% 0.153 260.8)
-
Step 800
800
#234B94
oklch(42.6% 0.129 261.2)
-
Step 900
900 (this color)
#18366B
oklch(34.2% 0.099 260.8)
-
Step 950
950
#142645
oklch(27.1% 0.063 260.6)
#18366B 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) | #1A3C6D | 0.019 |
| Deuteranopia (no green cones) | #05346A | 0.016 |
| Tritanopia (no blue cones) | #00434B | 0.079 |
| Achromatopsia (no color) | #383838 | 0.099 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #18366B
#18366B
oklch(34.2% 0.099 260.8)
- #4B3400
#4B3400
oklch(34.3% 0.071 81.3)
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 #18366B, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Marine Blue #01386A ΔE 0.015
- Prussian Blue #1D3557 ΔE 0.035
- Marine #042E60 ΔE 0.036
- Twilight Blue #0A437A ΔE 0.043
- Dark Blue Grey #1F3B4D ΔE 0.059
- Midnight Green #073B4C ΔE 0.063
- Dark Grey Blue #29465B ΔE 0.067
- Midnight Blue #191970 ΔE 0.074
Use #18366B 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.