#243587
Closest named color: Twilight Blue (#0A437A). oklch(36.9% 0.138 269.4), rgb(36, 53, 135).
Aa
White text reads best on this color (10.85:1).
About this color
#243587 is a dark, moderately saturated blue. In OKLCH its lightness is 37%, its chroma 0.138 and its hue 269°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.048 away. White text reads best on it, at 10.85:1.
| Hue family | Blues |
| Lightness | dark (37%) |
| Chroma | moderately saturated (0.138) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 1.93:1 |
| White text | 10.85:1 |
Values
| HEX | #243587 |
| RGB | rgb(36, 53, 135) |
| HSL | hsl(230, 58%, 34%) |
| OKLCH | oklch(36.9% 0.138 269.4) |
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 #243587 | 10.85:1 | AAA | Lc -98.6 | Preferred for body text |
| Black text on #243587 | 1.93:1 | Fails | Lc 9.2 | Not readable |
| #243587 text on white | 10.85:1 | AAA | Lc 94.7 | Preferred for body text |
| #243587 text on black | 1.93:1 | 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
#F2F5FF
oklch(97.1% 0.014 272.7)
-
Step 100
100
#E2EAFF
oklch(93.7% 0.03 269.1)
-
Step 200
200
#CAD8FF
oklch(88.4% 0.056 269.7)
-
Step 300
300
#A8BEFF
oklch(80.9% 0.096 269.8)
-
Step 400
400
#7B9AFF
oklch(70.8% 0.152 269.4)
-
Step 500
500
#5B7CFF
oklch(63.1% 0.198 269.4)
-
Step 600
600
#425DF7
oklch(55.6% 0.23 269.5)
-
Step 700
700
#354BD7
oklch(49.1% 0.214 269.5)
-
Step 800
800
#2B3FAE
oklch(42.7% 0.177 269.3)
-
Step 900
900 (this color)
#243587
oklch(36.9% 0.138 269.4)
-
Step 950
950
#162150
oklch(26.9% 0.087 269.7)
#243587 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) | #00428A | 0.038 |
| Deuteranopia (no green cones) | #003985 | 0.027 |
| Tritanopia (no blue cones) | #004958 | 0.111 |
| Achromatopsia (no color) | #3D3D3D | 0.139 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #243587
#243587
oklch(36.9% 0.138 269.4)
- #4F3D00
#4F3D00
oklch(36.9% 0.075 89.9)
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 #243587, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.048
- Cobalt #1E488F ΔE 0.051
- Marine Blue #01386A ΔE 0.059
- Sapphire #2138AB ΔE 0.060
- Dark Slate Blue #483D8B ΔE 0.061
- Blueberry #464196 ΔE 0.066
- Royal #0C1793 ΔE 0.072
- Light Navy #155084 ΔE 0.075
Use #243587 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.