#043A71
Closest named color: Marine Blue (#01386A). oklch(35.1% 0.108 254.2), rgb(4, 58, 113).
Aa
White text reads best on this color (11.35:1).
About this color
#043A71 is a dark, moderately saturated blue. In OKLCH its lightness is 35%, its chroma 0.108 and its hue 254°. Its hue sits on the cool side of the wheel. The nearest named color is Marine Blue (#01386A), ΔE 0.013 away. White text reads best on it, at 11.35:1.
| Hue family | Blues |
| Lightness | dark (35%) |
| Chroma | moderately saturated (0.108) |
| Temperature | cool |
| Nearest name | Marine Blue (#01386A) |
| Black text | 1.84:1 |
| White text | 11.35:1 |
Values
| HEX | #043A71 |
| RGB | rgb(4, 58, 113) |
| HSL | hsl(210, 93%, 23%) |
| OKLCH | oklch(35.1% 0.108 254.2) |
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 #043A71 | 11.35:1 | AAA | Lc -99.5 | Preferred for body text |
| Black text on #043A71 | 1.84:1 | Fails | Lc 8.2 | Not readable |
| #043A71 text on white | 11.35:1 | AAA | Lc 95.6 | Preferred for body text |
| #043A71 text on black | 1.84:1 | 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
#F1F6FD
oklch(97.1% 0.011 256.7)
-
Step 100
100
#DFEBFA
oklch(93.6% 0.024 254)
-
Step 200
200
#C5DBF7
oklch(88.4% 0.045 254.5)
-
Step 300
300
#9DC4F5
oklch(81% 0.081 254.4)
-
Step 400
400
#65A3F0
oklch(70.7% 0.131 254.6)
-
Step 500
500
#358AEA
oklch(63.1% 0.166 254.1)
-
Step 600
600
#0072D8
oklch(55.7% 0.178 254.2)
-
Step 700
700
#005FB7
oklch(49.1% 0.158 254.4)
-
Step 800
800
#004E97
oklch(42.8% 0.136 254.1)
-
Step 900
900 (this color)
#043A71
oklch(35.1% 0.108 254.2)
-
Step 950
950
#0B2747
oklch(27.1% 0.068 254.1)
#043A71 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) | #1B3F73 | 0.024 |
| Deuteranopia (no green cones) | #003670 | 0.013 |
| Tritanopia (no blue cones) | #004750 | 0.079 |
| Achromatopsia (no color) | #3A3A3A | 0.108 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #043A71
#043A71
oklch(35.1% 0.108 254.2)
- #513400
#513400
oklch(35.1% 0.074 74.8)
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 #043A71, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Marine Blue #01386A ΔE 0.013
- Twilight Blue #0A437A ΔE 0.030
- Marine #042E60 ΔE 0.045
- Prussian Blue #1D3557 ΔE 0.047
- Dark Blue Grey #1F3B4D ΔE 0.066
- Midnight Green #073B4C ΔE 0.067
- Cobalt #1E488F ΔE 0.067
- Dark Grey Blue #29465B ΔE 0.068
Use #043A71 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.