#003F6B
Closest named color: Marine Blue (#01386A). oklch(35.8% 0.095 247.3), rgb(0, 63, 107).
Aa
White text reads best on this color (10.91:1).
About this color
#003F6B is a dark, moderately saturated blue. In OKLCH its lightness is 36%, its chroma 0.095 and its hue 247°. Its hue sits on the cool side of the wheel. The nearest named color is Marine Blue (#01386A), ΔE 0.022 away. White text reads best on it, at 10.91:1.
| Hue family | Blues |
| Lightness | dark (36%) |
| Chroma | moderately saturated (0.095) |
| Temperature | cool |
| Nearest name | Marine Blue (#01386A) |
| Black text | 1.92:1 |
| White text | 10.91:1 |
Values
| HEX | #003F6B |
| RGB | rgb(0, 63, 107) |
| HSL | hsl(205, 100%, 21%) |
| OKLCH | oklch(35.8% 0.095 247.3) |
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 #003F6B | 10.91:1 | AAA | Lc -98.7 | Preferred for body text |
| Black text on #003F6B | 1.92:1 | Fails | Lc 9.2 | Not readable |
| #003F6B text on white | 10.91:1 | AAA | Lc 94.7 | Preferred for body text |
| #003F6B text on black | 1.92:1 | Fails | Lc -7.9 | 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
#DFECF7
oklch(93.7% 0.02 243.4)
-
Step 200
200
#C5DCF2
oklch(88.4% 0.039 247.1)
-
Step 300
300
#9CC6ED
oklch(81% 0.071 246.8)
-
Step 400
400
#63A7E4
oklch(70.8% 0.113 247.2)
-
Step 500
500
#2E8FDC
oklch(63.2% 0.145 247.2)
-
Step 600
600
#0078C4
oklch(55.7% 0.147 247.1)
-
Step 700
700
#0064A6
oklch(49.1% 0.131 247.6)
-
Step 800
800
#005289
oklch(42.7% 0.113 247.3)
-
Step 900
900 (this color)
#003F6B
oklch(35.8% 0.095 247.3)
-
Step 950
950
#092842
oklch(26.9% 0.06 247.8)
#003F6B 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) | #29426D | 0.034 |
| Deuteranopia (no green cones) | #18396A | 0.021 |
| Tritanopia (no blue cones) | #004A4F | 0.068 |
| Achromatopsia (no color) | #3D3D3D | 0.095 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #003F6B
#003F6B
oklch(35.8% 0.095 247.3)
- #573300
#573300
oklch(35.7% 0.079 67.7)
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 #003F6B, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Marine Blue #01386A ΔE 0.022
- Twilight Blue #0A437A ΔE 0.028
- Prussian Blue #1D3557 ΔE 0.043
- Dark Grey Blue #29465B ΔE 0.051
- Dark Blue Grey #1F3B4D ΔE 0.053
- Marine #042E60 ΔE 0.054
- Midnight Green #073B4C ΔE 0.054
- Charcoal #264653 ΔE 0.059
Use #003F6B 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.