#243E71
Closest named color: Twilight Blue (#0A437A). oklch(37.1% 0.093 262.4), rgb(36, 62, 113).
Aa
White text reads best on this color (10.48:1).
About this color
#243E71 is a dark, moderately saturated blue. In OKLCH its lightness is 37%, its chroma 0.093 and its hue 262°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.025 away. White text reads best on it, at 10.48:1.
| Hue family | Blues |
| Lightness | dark (37%) |
| Chroma | moderately saturated (0.093) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 2.00:1 |
| White text | 10.48:1 |
Values
| HEX | #243E71 |
| RGB | rgb(36, 62, 113) |
| HSL | hsl(220, 52%, 29%) |
| OKLCH | oklch(37.1% 0.093 262.4) |
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 #243E71 | 10.48:1 | AAA | Lc -98.1 | Preferred for body text |
| Black text on #243E71 | 2.00:1 | Fails | Lc 9.8 | Not readable |
| #243E71 text on white | 10.48:1 | AAA | Lc 94.1 | Preferred for body text |
| #243E71 text on black | 2.00:1 | Fails | Lc -8.4 | 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
#E3EAF8
oklch(93.6% 0.02 264.5)
-
Step 200
200
#CBDAF4
oklch(88.5% 0.039 261.5)
-
Step 300
300
#A8C1EF
oklch(80.8% 0.071 262.5)
-
Step 400
400
#7AA0E7
oklch(70.7% 0.113 262.3)
-
Step 500
500
#5987DF
oklch(63.2% 0.142 262.2)
-
Step 600
600
#3F6ECD
oklch(55.5% 0.156 262.6)
-
Step 700
700
#315CB2
oklch(49.2% 0.145 262.4)
-
Step 800
800
#294B90
oklch(42.6% 0.121 262.7)
-
Step 900
900 (this color)
#243E71
oklch(37.1% 0.093 262.4)
-
Step 950
950
#162643
oklch(27.1% 0.058 261.5)
#243E71 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) | #264373 | 0.016 |
| Deuteranopia (no green cones) | #1A3C70 | 0.013 |
| Tritanopia (no blue cones) | #004A52 | 0.078 |
| Achromatopsia (no color) | #3F3F3F | 0.094 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #243E71
#243E71
oklch(37.1% 0.093 262.4)
- #543B00
#543B00
oklch(37.1% 0.076 81.7)
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 #243E71, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.025
- Marine Blue #01386A ΔE 0.037
- Dark Grey Blue #29465B ΔE 0.051
- Prussian Blue #1D3557 ΔE 0.051
- Cobalt #1E488F ΔE 0.054
- Light Navy #155084 ΔE 0.057
- Dark Blue Grey #1F3B4D ΔE 0.063
- Charcoal #264653 ΔE 0.064
Use #243E71 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.