#243F69
Closest named color: Twilight Blue (#0A437A). oklch(36.8% 0.08 258.9), rgb(36, 63, 105).
Aa
White text reads best on this color (10.55:1).
About this color
#243F69 is a dark, moderately saturated blue. In OKLCH its lightness is 37%, its chroma 0.080 and its hue 259°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.033 away. White text reads best on it, at 10.55:1.
| Hue family | Blues |
| Lightness | dark (37%) |
| Chroma | moderately saturated (0.080) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 1.99:1 |
| White text | 10.55:1 |
Values
| HEX | #243F69 |
| RGB | rgb(36, 63, 105) |
| HSL | hsl(217, 49%, 28%) |
| OKLCH | oklch(36.8% 0.08 258.9) |
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 #243F69 | 10.55:1 | AAA | Lc -98.3 | Preferred for body text |
| Black text on #243F69 | 1.99:1 | Fails | Lc 9.6 | Not readable |
| #243F69 text on white | 10.55:1 | AAA | Lc 94.3 | Preferred for body text |
| #243F69 text on black | 1.99:1 | Fails | Lc -8.3 | 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
#F2F6FB
oklch(97.2% 0.008 253.9)
-
Step 100
100
#E3EAF6
oklch(93.5% 0.018 261.3)
-
Step 200
200
#CCDAF0
oklch(88.5% 0.034 259.4)
-
Step 300
300
#AAC2E8
oklch(80.9% 0.06 259.5)
-
Step 400
400
#7CA2DC
oklch(70.7% 0.095 258.6)
-
Step 500
500
#5A8AD3
oklch(63.2% 0.122 258.5)
-
Step 600
600
#4072C0
oklch(55.6% 0.133 259)
-
Step 700
700
#325FA6
oklch(49.1% 0.124 259.2)
-
Step 800
800
#2A4E86
oklch(42.7% 0.102 259)
-
Step 900
900 (this color)
#243F69
oklch(36.8% 0.08 258.9)
-
Step 950
950
#17263F
oklch(26.9% 0.051 260.2)
#243F69 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) | #2D426B | 0.016 |
| Deuteranopia (no green cones) | #233C68 | 0.009 |
| Tritanopia (no blue cones) | #00494F | 0.067 |
| Achromatopsia (no color) | #3F3F3F | 0.080 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #243F69
#243F69
oklch(36.8% 0.08 258.9)
- #553A00
#553A00
oklch(37% 0.077 79.3)
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 #243F69, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.033
- Marine Blue #01386A ΔE 0.038
- Dark Grey Blue #29465B ΔE 0.038
- Prussian Blue #1D3557 ΔE 0.043
- Charcoal #264653 ΔE 0.050
- Dark Blue Grey #1F3B4D ΔE 0.050
- Midnight Green #073B4C ΔE 0.059
- Light Navy #155084 ΔE 0.061
Use #243F69 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.