#243C82
Closest named color: Twilight Blue (#0A437A). oklch(38% 0.122 266.4), rgb(36, 60, 130).
Aa
White text reads best on this color (10.27:1).
About this color
#243C82 is a dark, moderately saturated blue. In OKLCH its lightness is 38%, its chroma 0.122 and its hue 266°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.030 away. White text reads best on it, at 10.27:1.
| Hue family | Blues |
| Lightness | dark (38%) |
| Chroma | moderately saturated (0.122) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 2.04:1 |
| White text | 10.27:1 |
Values
| HEX | #243C82 |
| RGB | rgb(36, 60, 130) |
| HSL | hsl(225, 57%, 33%) |
| OKLCH | oklch(38% 0.122 266.4) |
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 #243C82 | 10.27:1 | AAA | Lc -97.6 | Preferred for body text |
| Black text on #243C82 | 2.04:1 | Fails | Lc 10.4 | Not readable |
| #243C82 text on white | 10.27:1 | AAA | Lc 93.5 | Preferred for body text |
| #243C82 text on black | 2.04:1 | Fails | Lc -9.0 | 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
#F2F5FE
oklch(97% 0.012 271.3)
-
Step 100
100
#E2EAFC
oklch(93.6% 0.026 266.6)
-
Step 200
200
#CAD9FC
oklch(88.5% 0.051 267)
-
Step 300
300
#A5C0FC
oklch(80.9% 0.09 265.7)
-
Step 400
400
#769CFB
oklch(70.7% 0.146 266.3)
-
Step 500
500
#5580F9
oklch(63.2% 0.187 266.4)
-
Step 600
600
#3C65E8
oklch(55.5% 0.204 266.5)
-
Step 700
700
#2F53CA
oklch(49.1% 0.189 266.4)
-
Step 800
800
#2745A3
oklch(42.7% 0.156 266.3)
-
Step 900
900 (this color)
#243C82
oklch(38% 0.122 266.4)
-
Step 950
950
#15234C
oklch(27% 0.078 266.9)
#243C82 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) | #0E4584 | 0.027 |
| Deuteranopia (no green cones) | #003C81 | 0.025 |
| Tritanopia (no blue cones) | #004D59 | 0.099 |
| Achromatopsia (no color) | #414141 | 0.122 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #243C82
#243C82
oklch(38% 0.122 266.4)
- #543F00
#543F00
oklch(38% 0.078 87.2)
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 #243C82, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.030
- Cobalt #1E488F ΔE 0.037
- Marine Blue #01386A ΔE 0.052
- Dark Slate Blue #483D8B ΔE 0.055
- Light Navy #155084 ΔE 0.057
- Blueberry #464196 ΔE 0.061
- Dusk Blue #26538D ΔE 0.067
- Sapphire #2138AB ΔE 0.069
Use #243C82 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.