#243557
Closest named color: Prussian Blue (#1D3557). oklch(33.2% 0.064 263.2), rgb(36, 53, 87).
Aa
White text reads best on this color (12.19:1).
About this color
#243557 is a dark, muted blue. In OKLCH its lightness is 33%, its chroma 0.064 and its hue 263°. Its hue sits on the cool side of the wheel. The nearest named color is Prussian Blue (#1D3557), ΔE 0.009 away. White text reads best on it, at 12.19:1.
| Hue family | Blues |
| Lightness | dark (33%) |
| Chroma | muted (0.064) |
| Temperature | cool |
| Nearest name | Prussian Blue (#1D3557) |
| Black text | 1.72:1 |
| White text | 12.19:1 |
Values
| HEX | #243557 |
| RGB | rgb(36, 53, 87) |
| HSL | hsl(220, 41%, 24%) |
| OKLCH | oklch(33.2% 0.064 263.2) |
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 #243557 | 12.19:1 | AAA | Lc -101.2 | Preferred for body text |
| Black text on #243557 | 1.72:1 | Fails | Lc 0.0 | Not readable |
| #243557 text on white | 12.19:1 | AAA | Lc 97.7 | Preferred for body text |
| #243557 text on black | 1.72:1 | Fails | Lc 0.0 | 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
#F3F5FA
oklch(97% 0.007 268.5)
-
Step 100
100
#E5EAF4
oklch(93.6% 0.015 264.5)
-
Step 200
200
#D0DAEC
oklch(88.6% 0.027 262.3)
-
Step 300
300
#B0C1E1
oklch(80.9% 0.049 263.1)
-
Step 400
400
#87A1D2
oklch(70.7% 0.078 262.8)
-
Step 500
500
#6A89C6
oklch(63.2% 0.099 263.2)
-
Step 600
600
#5172B2
oklch(55.6% 0.107 262.7)
-
Step 700
700
#425F99
oklch(49.1% 0.1 263.1)
-
Step 800
800
#374E7C
oklch(42.8% 0.082 263.2)
-
Step 900
900 (this color)
#243557
oklch(33.2% 0.064 263.2)
-
Step 950
950
#1C263B
oklch(27% 0.042 264.3)
#243557 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) | #273858 | 0.011 |
| Deuteranopia (no green cones) | #213356 | 0.008 |
| Tritanopia (no blue cones) | #083C41 | 0.058 |
| Achromatopsia (no color) | #353535 | 0.065 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #243557
#243557
oklch(33.2% 0.064 263.2)
- #463205
#463205
oklch(33.2% 0.064 82.3)
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 #243557, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Prussian Blue #1D3557 ΔE 0.009
- Dark Blue Grey #1F3B4D ΔE 0.030
- Gunmetal #293241 ΔE 0.039
- Midnight Green #073B4C ΔE 0.040
- Space Cadet #2B2D42 ΔE 0.040
- Marine Blue #01386A ΔE 0.041
- Marine #042E60 ΔE 0.044
- Onyx #343A40 ΔE 0.053
Use #243557 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.