#043757
Closest named color: Prussian Blue (#1D3557). oklch(32.4% 0.075 243.3), rgb(4, 55, 87).
Aa
White text reads best on this color (12.43:1).
About this color
#043757 is a dark, moderately saturated blue. In OKLCH its lightness is 32%, its chroma 0.075 and its hue 243°. Its hue sits on the cool side of the wheel. The nearest named color is Prussian Blue (#1D3557), ΔE 0.019 away. White text reads best on it, at 12.43:1.
| Hue family | Blues |
| Lightness | dark (32%) |
| Chroma | moderately saturated (0.075) |
| Temperature | cool |
| Nearest name | Prussian Blue (#1D3557) |
| Black text | 1.68:1 |
| White text | 12.43:1 |
Values
| HEX | #043757 |
| RGB | rgb(4, 55, 87) |
| HSL | hsl(203, 91%, 18%) |
| OKLCH | oklch(32.4% 0.075 243.3) |
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 #043757 | 12.43:1 | AAA | Lc -101.3 | Preferred for body text |
| Black text on #043757 | 1.68:1 | Fails | Lc 0.0 | Not readable |
| #043757 text on white | 12.43:1 | AAA | Lc 97.9 | Preferred for body text |
| #043757 text on black | 1.68:1 | 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
#F1F6FA
oklch(97.1% 0.008 241.7)
-
Step 100
100
#E1EBF4
oklch(93.5% 0.016 245.1)
-
Step 200
200
#C8DCED
oklch(88.5% 0.032 243.7)
-
Step 300
300
#A2C6E3
oklch(81% 0.056 242.7)
-
Step 400
400
#6DA7D5
oklch(70.6% 0.091 243.5)
-
Step 500
500
#4290CA
oklch(63% 0.116 243.7)
-
Step 600
600
#1A7AB7
oklch(55.7% 0.126 243.2)
-
Step 700
700
#07669D
oklch(49.1% 0.117 243.3)
-
Step 800
800
#0E537F
oklch(42.5% 0.097 243.4)
-
Step 900
900 (this color)
#043757
oklch(32.4% 0.075 243.3)
-
Step 950
950
#0F293C
oklch(27.1% 0.048 243)
#043757 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) | #283858 | 0.034 |
| Deuteranopia (no green cones) | #1C3156 | 0.024 |
| Tritanopia (no blue cones) | #003F43 | 0.051 |
| Achromatopsia (no color) | #343434 | 0.075 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #043757
#043757
oklch(32.4% 0.075 243.3)
- #4D2A00
#4D2A00
oklch(32.3% 0.073 63.8)
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 #043757, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Prussian Blue #1D3557 ΔE 0.019
- Midnight Green #073B4C ΔE 0.027
- Dark Blue Grey #1F3B4D ΔE 0.033
- Marine Blue #01386A ΔE 0.033
- Marine #042E60 ΔE 0.035
- Gunmetal #293241 ΔE 0.049
- Space Cadet #2B2D42 ΔE 0.054
- Dark Grey Blue #29465B ΔE 0.062
Use #043757 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.