#3F478B
Closest named color: Blueberry (#464196). oklch(42.7% 0.112 275.6), rgb(63, 71, 139).
Aa
White text reads best on this color (8.44:1).
About this color
#3F478B is a dark, moderately saturated blue. In OKLCH its lightness is 43%, its chroma 0.112 and its hue 276°. Its hue sits on the cool side of the wheel. The nearest named color is Blueberry (#464196), ΔE 0.027 away. White text reads best on it, at 8.44:1.
| Hue family | Blues |
| Lightness | dark (43%) |
| Chroma | moderately saturated (0.112) |
| Temperature | cool |
| Nearest name | Blueberry (#464196) |
| Black text | 2.48:1 |
| White text | 8.44:1 |
Values
| HEX | #3F478B |
| RGB | rgb(63, 71, 139) |
| HSL | hsl(234, 38%, 40%) |
| OKLCH | oklch(42.7% 0.112 275.6) |
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 #3F478B | 8.44:1 | AAA | Lc -93.5 | Preferred for body text |
| Black text on #3F478B | 2.48:1 | Fails | Lc 15.1 | Dividers and decoration only |
| #3F478B text on white | 8.44:1 | AAA | Lc 88.9 | Fine for body text |
| #3F478B text on black | 2.48:1 | Fails | Lc -13.3 | 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 800.
-
Step 50
50
#F4F5FB
oklch(97.1% 0.008 278.6)
-
Step 100
100
#E6E9F7
oklch(93.6% 0.019 276.3)
-
Step 200
200
#D2D8F2
oklch(88.6% 0.036 275.3)
-
Step 300
300
#B4BEEB
oklch(80.9% 0.065 275.1)
-
Step 400
400
#8E9BE2
oklch(70.7% 0.105 275.4)
-
Step 500
500
#7481D9
oklch(63.2% 0.133 275.6)
-
Step 600
600
#5D68C7
oklch(55.6% 0.146 275.6)
-
Step 700
700
#4D56AC
oklch(49.1% 0.136 275.7)
-
Step 800
800 (this color)
#3F478B
oklch(42.7% 0.112 275.6)
-
Step 900
900
#353C6F
oklch(37.7% 0.087 275.5)
-
Step 950
950
#1F2441
oklch(27.1% 0.054 274.8)
#3F478B 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) | #28508D | 0.034 |
| Deuteranopia (no green cones) | #1F4A8A | 0.036 |
| Tritanopia (no blue cones) | #1C5662 | 0.099 |
| Achromatopsia (no color) | #4D4D4D | 0.112 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3F478B
#3F478B
oklch(42.7% 0.112 275.6)
- #5E4E00
#5E4E00
oklch(42.8% 0.088 95.4)
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 #3F478B, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Blueberry #464196 ΔE 0.027
- Dark Slate Blue #483D8B ΔE 0.028
- Cobalt #1E488F ΔE 0.037
- Twilight #4E518B ΔE 0.038
- Dusk Blue #26538D ΔE 0.040
- Light Navy #155084 ΔE 0.049
- Dusk #4E5481 ΔE 0.051
- Denim Blue #3B5B92 ΔE 0.056
Use #3F478B 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.