#003F63
Closest named color: Marine Blue (#01386A). oklch(35.3% 0.084 242.3), rgb(0, 63, 99).
Aa
White text reads best on this color (11.10:1).
About this color
#003F63 is a dark, moderately saturated blue. In OKLCH its lightness is 35%, its chroma 0.084 and its hue 242°. Its hue sits on the cool side of the wheel. The nearest named color is Marine Blue (#01386A), ΔE 0.027 away. White text reads best on it, at 11.10:1.
| Hue family | Blues |
| Lightness | dark (35%) |
| Chroma | moderately saturated (0.084) |
| Temperature | cool |
| Nearest name | Marine Blue (#01386A) |
| Black text | 1.89:1 |
| White text | 11.10:1 |
Values
| HEX | #003F63 |
| RGB | rgb(0, 63, 99) |
| HSL | hsl(202, 100%, 19%) |
| OKLCH | oklch(35.3% 0.084 242.3) |
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 #003F63 | 11.10:1 | AAA | Lc -99.0 | Preferred for body text |
| Black text on #003F63 | 1.89:1 | Fails | Lc 8.7 | Not readable |
| #003F63 text on white | 11.10:1 | AAA | Lc 95.2 | Preferred for body text |
| #003F63 text on black | 1.89:1 | Fails | Lc -7.5 | 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
#F1F6FB
oklch(97.1% 0.009 247.9)
-
Step 100
100
#E0ECF5
oklch(93.7% 0.018 240)
-
Step 200
200
#C6DDEF
oklch(88.6% 0.035 241.5)
-
Step 300
300
#9DC6E7
oklch(80.8% 0.064 242.9)
-
Step 400
400
#65A8DA
oklch(70.7% 0.1 242.3)
-
Step 500
500
#3291D0
oklch(63.1% 0.129 242.3)
-
Step 600
600
#007ABA
oklch(55.6% 0.133 242.5)
-
Step 700
700
#00669D
oklch(49% 0.118 242.7)
-
Step 800
800
#005482
oklch(42.8% 0.102 242.4)
-
Step 900
900 (this color)
#003F63
oklch(35.3% 0.084 242.3)
-
Step 950
950
#0A293E
oklch(27% 0.053 242.3)
#003F63 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) | #2D4065 | 0.038 |
| Deuteranopia (no green cones) | #203862 | 0.028 |
| Tritanopia (no blue cones) | #00484C | 0.057 |
| Achromatopsia (no color) | #3C3C3C | 0.084 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #003F63
#003F63
oklch(35.3% 0.084 242.3)
- #583000
#583000
oklch(35.3% 0.081 62.8)
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 #003F63, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Marine Blue #01386A ΔE 0.027
- Prussian Blue #1D3557 ΔE 0.036
- Midnight Green #073B4C ΔE 0.040
- Dark Blue Grey #1F3B4D ΔE 0.040
- Twilight Blue #0A437A ΔE 0.041
- Dark Grey Blue #29465B ΔE 0.044
- Charcoal #264653 ΔE 0.049
- Marine #042E60 ΔE 0.053
Use #003F63 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.