#243B6C
Closest named color: Marine Blue (#01386A). oklch(36.1% 0.09 263.6), rgb(36, 59, 108).
Aa
White text reads best on this color (10.95:1).
About this color
#243B6C is a dark, moderately saturated blue. In OKLCH its lightness is 36%, its chroma 0.090 and its hue 264°. Its hue sits on the cool side of the wheel. The nearest named color is Marine Blue (#01386A), ΔE 0.031 away. White text reads best on it, at 10.95:1.
| Hue family | Blues |
| Lightness | dark (36%) |
| Chroma | moderately saturated (0.090) |
| Temperature | cool |
| Nearest name | Marine Blue (#01386A) |
| Black text | 1.91:1 |
| White text | 10.95:1 |
Values
| HEX | #243B6C |
| RGB | rgb(36, 59, 108) |
| HSL | hsl(221, 50%, 28%) |
| OKLCH | oklch(36.1% 0.09 263.6) |
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 #243B6C | 10.95:1 | AAA | Lc -99.0 | Preferred for body text |
| Black text on #243B6C | 1.91:1 | Fails | Lc 8.8 | Not readable |
| #243B6C text on white | 10.95:1 | AAA | Lc 95.1 | Preferred for body text |
| #243B6C text on black | 1.91:1 | Fails | Lc -7.5 | 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
#E3EAF7
oklch(93.6% 0.019 263)
-
Step 200
200
#CDDAF3
oklch(88.6% 0.037 263.6)
-
Step 300
300
#AAC1ED
oklch(80.9% 0.067 263.3)
-
Step 400
400
#7EA0E4
oklch(70.8% 0.107 263.5)
-
Step 500
500
#5D86DC
oklch(63% 0.138 263.7)
-
Step 600
600
#446ECA
oklch(55.5% 0.15 263.8)
-
Step 700
700
#365CAF
oklch(49.2% 0.139 263.6)
-
Step 800
800
#2D4B8D
oklch(42.6% 0.115 263.8)
-
Step 900
900 (this color)
#243B6C
oklch(36.1% 0.09 263.6)
-
Step 950
950
#182542
oklch(26.9% 0.057 264.6)
#243B6C 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) | #24406E | 0.015 |
| Deuteranopia (no green cones) | #19396B | 0.014 |
| Tritanopia (no blue cones) | #00464E | 0.075 |
| Achromatopsia (no color) | #3C3C3C | 0.090 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #243B6C
#243B6C
oklch(36.1% 0.09 263.6)
- #503900
#503900
oklch(36.1% 0.074 83.2)
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 #243B6C, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Marine Blue #01386A ΔE 0.031
- Twilight Blue #0A437A ΔE 0.033
- Prussian Blue #1D3557 ΔE 0.041
- Dark Grey Blue #29465B ΔE 0.051
- Dark Blue Grey #1F3B4D ΔE 0.056
- Marine #042E60 ΔE 0.056
- Charcoal #264653 ΔE 0.063
- Midnight Green #073B4C ΔE 0.065
Use #243B6C 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.