#243D6C
Closest named color: Twilight Blue (#0A437A). oklch(36.6% 0.087 261.9), rgb(36, 61, 108).
Aa
White text reads best on this color (10.71:1).
About this color
#243D6C is a dark, moderately saturated blue. In OKLCH its lightness is 37%, its chroma 0.087 and its hue 262°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.031 away. White text reads best on it, at 10.71:1.
| Hue family | Blues |
| Lightness | dark (37%) |
| Chroma | moderately saturated (0.087) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 1.95:1 |
| White text | 10.71:1 |
Values
| HEX | #243D6C |
| RGB | rgb(36, 61, 108) |
| HSL | hsl(219, 50%, 28%) |
| OKLCH | oklch(36.6% 0.087 261.9) |
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 #243D6C | 10.71:1 | AAA | Lc -98.6 | Preferred for body text |
| Black text on #243D6C | 1.95:1 | Fails | Lc 9.3 | Not readable |
| #243D6C text on white | 10.71:1 | AAA | Lc 94.7 | Preferred for body text |
| #243D6C text on black | 1.95:1 | Fails | Lc -7.9 | 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
#CCDAF2
oklch(88.5% 0.036 261.3)
-
Step 300
300
#AAC1EC
oklch(80.8% 0.066 262.8)
-
Step 400
400
#7CA1E2
oklch(70.8% 0.104 261.3)
-
Step 500
500
#5B88DA
oklch(63.2% 0.134 261.6)
-
Step 600
600
#4270C7
oklch(55.7% 0.144 261.9)
-
Step 700
700
#345DAC
oklch(49.1% 0.135 262)
-
Step 800
800
#2B4C8B
oklch(42.6% 0.112 262)
-
Step 900
900 (this color)
#243D6C
oklch(36.6% 0.087 261.9)
-
Step 950
950
#172641
oklch(27% 0.055 261.4)
#243D6C 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) | #28416E | 0.014 |
| Deuteranopia (no green cones) | #1D3B6B | 0.011 |
| Tritanopia (no blue cones) | #00484F | 0.074 |
| Achromatopsia (no color) | #3E3E3E | 0.087 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #243D6C
#243D6C
oklch(36.6% 0.087 261.9)
- #523A00
#523A00
oklch(36.6% 0.075 82.4)
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 #243D6C, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.031
- Marine Blue #01386A ΔE 0.034
- Prussian Blue #1D3557 ΔE 0.043
- Dark Grey Blue #29465B ΔE 0.046
- Dark Blue Grey #1F3B4D ΔE 0.055
- Charcoal #264653 ΔE 0.058
- Marine #042E60 ΔE 0.061
- Cobalt #1E488F ΔE 0.063
Use #243D6C 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.