#042F59
Closest named color: Marine (#042E60). oklch(30.4% 0.088 252.7), rgb(4, 47, 89).
Aa
White text reads best on this color (13.49:1).
About this color
#042F59 is a dark, moderately saturated blue. In OKLCH its lightness is 30%, its chroma 0.088 and its hue 253°. Its hue sits on the cool side of the wheel. The nearest named color is Marine (#042E60), ΔE 0.013 away. White text reads best on it, at 13.49:1.
| Hue family | Blues |
| Lightness | dark (30%) |
| Chroma | moderately saturated (0.088) |
| Temperature | cool |
| Nearest name | Marine (#042E60) |
| Black text | 1.55:1 |
| White text | 13.49:1 |
Values
| HEX | #042F59 |
| RGB | rgb(4, 47, 89) |
| HSL | hsl(210, 91%, 18%) |
| OKLCH | oklch(30.4% 0.088 252.7) |
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 #042F59 | 13.49:1 | AAA | Lc -102.8 | Preferred for body text |
| Black text on #042F59 | 1.55:1 | Fails | Lc 0.0 | Not readable |
| #042F59 text on white | 13.49:1 | AAA | Lc 99.6 | Preferred for body text |
| #042F59 text on black | 1.55:1 | 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 950.
-
Step 50
50
#EFF6FF
oklch(97% 0.014 254.6)
-
Step 100
100
#DCECFE
oklch(93.7% 0.03 251.3)
-
Step 200
200
#BFDCFF
oklch(88.5% 0.058 253.3)
-
Step 300
300
#93C5FF
oklch(81% 0.098 252.7)
-
Step 400
400
#50A4FF
oklch(70.8% 0.157 252.5)
-
Step 500
500
#0089F9
oklch(63% 0.193 252.8)
-
Step 600
600
#0073D2
oklch(55.5% 0.17 252.7)
-
Step 700
700
#0061B2
oklch(49.2% 0.149 252.5)
-
Step 800
800
#004F93
oklch(42.7% 0.13 252.6)
-
Step 900
900
#00427C
oklch(37.8% 0.114 252.4)
-
Step 950
950 (this color)
#042F59
oklch(30.4% 0.088 252.7)
#042F59 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) | #19325B | 0.021 |
| Deuteranopia (no green cones) | #072B58 | 0.012 |
| Tritanopia (no blue cones) | #00393F | 0.065 |
| Achromatopsia (no color) | #2E2E2E | 0.088 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #042F59
#042F59
oklch(30.4% 0.088 252.7)
- #422900
#422900
oklch(30.5% 0.065 73.8)
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 #042F59, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Marine #042E60 ΔE 0.013
- Prussian Blue #1D3557 ΔE 0.032
- Marine Blue #01386A ΔE 0.038
- Midnight Green #073B4C ΔE 0.051
- Dark Blue Grey #1F3B4D ΔE 0.056
- Space Cadet #2B2D42 ΔE 0.057
- Oxford Blue #1B263B ΔE 0.058
- Gunmetal #293241 ΔE 0.059
Use #042F59 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.