#3F4E78
Closest named color: Dusk (#4E5481). oklch(43.1% 0.072 268.3), rgb(63, 78, 120).
Aa
White text reads best on this color (8.16:1).
About this color
#3F4E78 is a dark, moderately saturated blue. In OKLCH its lightness is 43%, its chroma 0.072 and its hue 268°. Its hue sits on the cool side of the wheel. The nearest named color is Dusk (#4E5481), ΔE 0.032 away. White text reads best on it, at 8.16:1.
| Hue family | Blues |
| Lightness | dark (43%) |
| Chroma | moderately saturated (0.072) |
| Temperature | cool |
| Nearest name | Dusk (#4E5481) |
| Black text | 2.57:1 |
| White text | 8.16:1 |
Values
| HEX | #3F4E78 |
| RGB | rgb(63, 78, 120) |
| HSL | hsl(224, 31%, 36%) |
| OKLCH | oklch(43.1% 0.072 268.3) |
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 #3F4E78 | 8.16:1 | AAA | Lc -92.8 | Preferred for body text |
| Black text on #3F4E78 | 2.57:1 | Fails | Lc 15.8 | Dividers and decoration only |
| #3F4E78 text on white | 8.16:1 | AAA | Lc 88.2 | Fine for body text |
| #3F4E78 text on black | 2.57:1 | Fails | Lc -14.0 | 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 800.
-
Step 50
50
#F4F5F9
oklch(97.1% 0.005 275)
-
Step 100
100
#E6EAF2
oklch(93.6% 0.012 264.5)
-
Step 200
200
#D2D9E9
oklch(88.5% 0.023 266.9)
-
Step 300
300
#B5C0DD
oklch(80.9% 0.043 269)
-
Step 400
400
#8FA0CC
oklch(70.8% 0.067 268.2)
-
Step 500
500
#7387BE
oklch(63% 0.087 268.5)
-
Step 600
600
#5C71AB
oklch(55.7% 0.094 268.1)
-
Step 700
700
#4C5E93
oklch(49.1% 0.088 268.8)
-
Step 800
800 (this color)
#3F4E78
oklch(43.1% 0.072 268.3)
-
Step 900
900
#354060
oklch(37.7% 0.057 269.1)
-
Step 950
950
#1F2638
oklch(27.1% 0.035 267.7)
#3F4E78 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) | #3F527A | 0.012 |
| Deuteranopia (no green cones) | #394D77 | 0.009 |
| Tritanopia (no blue cones) | #2A575D | 0.066 |
| Achromatopsia (no color) | #4F4F4F | 0.073 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3F4E78
#3F4E78
oklch(43.1% 0.072 268.3)
- #604D1A
#604D1A
oklch(42.9% 0.072 88.2)
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 #3F4E78, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dusk #4E5481 ΔE 0.032
- YInMn Blue #415A77 ΔE 0.038
- Twilight #4E518B ΔE 0.040
- Light Navy Blue #2E5A88 ΔE 0.041
- Dusk Blue #26538D ΔE 0.042
- Light Navy #155084 ΔE 0.043
- Dusty Grape #545775 ΔE 0.044
- Deep Sea Blue #015482 ΔE 0.049
Use #3F4E78 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.