#3F428E
Closest named color: Blueberry (#464196). oklch(41.9% 0.123 277.9), rgb(63, 66, 142).
Aa
White text reads best on this color (8.81:1).
About this color
#3F428E is a dark, moderately saturated blue. In OKLCH its lightness is 42%, its chroma 0.123 and its hue 278°. Its hue sits on the cool side of the wheel. The nearest named color is Blueberry (#464196), ΔE 0.017 away. White text reads best on it, at 8.81:1.
| Hue family | Blues |
| Lightness | dark (42%) |
| Chroma | moderately saturated (0.123) |
| Temperature | cool |
| Nearest name | Blueberry (#464196) |
| Black text | 2.38:1 |
| White text | 8.81:1 |
Values
| HEX | #3F428E |
| RGB | rgb(63, 66, 142) |
| HSL | hsl(238, 39%, 40%) |
| OKLCH | oklch(41.9% 0.123 277.9) |
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 #3F428E | 8.81:1 | AAA | Lc -94.4 | Preferred for body text |
| Black text on #3F428E | 2.38:1 | Fails | Lc 14.1 | Not readable |
| #3F428E text on white | 8.81:1 | AAA | Lc 89.9 | Fine for body text |
| #3F428E text on black | 2.38:1 | Fails | Lc -12.3 | 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
#F4F5FC
oklch(97.1% 0.009 279.7)
-
Step 100
100
#E6E9F8
oklch(93.6% 0.02 276.9)
-
Step 200
200
#D2D7F4
oklch(88.4% 0.04 277.8)
-
Step 300
300
#B5BDEF
oklch(80.9% 0.071 277.6)
-
Step 400
400
#9099E8
oklch(70.7% 0.116 278)
-
Step 500
500
#767EE1
oklch(63.2% 0.147 277.8)
-
Step 600
600
#6065CE
oklch(55.6% 0.159 277.8)
-
Step 700
700
#5053B3
oklch(49.2% 0.149 278)
-
Step 800
800 (this color)
#3F428E
oklch(41.9% 0.123 277.9)
-
Step 900
900
#373A73
oklch(37.6% 0.096 278.5)
-
Step 950
950
#202344
oklch(27.2% 0.061 277.6)
#3F428E 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) | #194E91 | 0.047 |
| Deuteranopia (no green cones) | #0B478C | 0.050 |
| Tritanopia (no blue cones) | #195361 | 0.108 |
| Achromatopsia (no color) | #4A4A4A | 0.124 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3F428E
#3F428E
oklch(41.9% 0.123 277.9)
- #5A4D00
#5A4D00
oklch(42.1% 0.087 98)
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 #3F428E, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Blueberry #464196 ΔE 0.017
- Dark Slate Blue #483D8B ΔE 0.018
- Cobalt #1E488F ΔE 0.039
- Twilight #4E518B ΔE 0.051
- Dusk Blue #26538D ΔE 0.052
- Light Navy #155084 ΔE 0.058
- Twilight Blue #0A437A ΔE 0.065
- Dusk #4E5481 ΔE 0.065
Use #3F428E 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.