#003665
Closest named color: Marine Blue (#01386A). oklch(33% 0.097 251.4), rgb(0, 54, 101).
Aa
White text reads best on this color (12.24:1).
About this color
#003665 is a dark, moderately saturated blue. In OKLCH its lightness is 33%, its chroma 0.097 and its hue 251°. Its hue sits on the cool side of the wheel. The nearest named color is Marine Blue (#01386A), ΔE 0.010 away. White text reads best on it, at 12.24:1.
| Hue family | Blues |
| Lightness | dark (33%) |
| Chroma | moderately saturated (0.097) |
| Temperature | cool |
| Nearest name | Marine Blue (#01386A) |
| Black text | 1.71:1 |
| White text | 12.24:1 |
Values
| HEX | #003665 |
| RGB | rgb(0, 54, 101) |
| HSL | hsl(208, 100%, 20%) |
| OKLCH | oklch(33% 0.097 251.4) |
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 #003665 | 12.24:1 | AAA | Lc -100.9 | Preferred for body text |
| Black text on #003665 | 1.71:1 | Fails | Lc 0.0 | Not readable |
| #003665 text on white | 12.24:1 | AAA | Lc 97.4 | Preferred for body text |
| #003665 text on black | 1.71:1 | 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
#F1F6FC
oklch(97.1% 0.01 252.8)
-
Step 100
100
#E0EBF8
oklch(93.6% 0.021 252.5)
-
Step 200
200
#C6DCF4
oklch(88.6% 0.041 250.6)
-
Step 300
300
#9EC4EF
oklch(80.8% 0.074 251.8)
-
Step 400
400
#67A5E7
oklch(70.7% 0.117 251.2)
-
Step 500
500
#398CE0
oklch(63% 0.15 251.7)
-
Step 600
600
#0475CE
oklch(55.7% 0.162 251.3)
-
Step 700
700
#0062AF
oklch(49.2% 0.144 251.3)
-
Step 800
800
#025090
oklch(42.7% 0.124 251.4)
-
Step 900
900 (this color)
#003665
oklch(33% 0.097 251.4)
-
Step 950
950
#0C2743
oklch(26.8% 0.062 251.9)
#003665 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) | #1D3A67 | 0.026 |
| Deuteranopia (no green cones) | #073164 | 0.015 |
| Tritanopia (no blue cones) | #004148 | 0.070 |
| Achromatopsia (no color) | #353535 | 0.097 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #003665
#003665
oklch(33% 0.097 251.4)
- #4C2E00
#4C2E00
oklch(33% 0.071 70.9)
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 #003665, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Marine Blue #01386A ΔE 0.010
- Marine #042E60 ΔE 0.025
- Prussian Blue #1D3557 ΔE 0.031
- Midnight Green #073B4C ΔE 0.051
- Twilight Blue #0A437A ΔE 0.052
- Dark Blue Grey #1F3B4D ΔE 0.054
- Gunmetal #293241 ΔE 0.070
- Dark Grey Blue #29465B ΔE 0.070
Use #003665 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.