#3F4C79
Closest named color: Dusk (#4E5481). oklch(42.7% 0.077 270.7), rgb(63, 76, 121).
Aa
White text reads best on this color (8.32:1).
About this color
#3F4C79 is a dark, moderately saturated blue. In OKLCH its lightness is 43%, its chroma 0.077 and its hue 271°. Its hue sits on the cool side of the wheel. The nearest named color is Dusk (#4E5481), ΔE 0.035 away. White text reads best on it, at 8.32:1.
| Hue family | Blues |
| Lightness | dark (43%) |
| Chroma | moderately saturated (0.077) |
| Temperature | cool |
| Nearest name | Dusk (#4E5481) |
| Black text | 2.52:1 |
| White text | 8.32:1 |
Values
| HEX | #3F4C79 |
| RGB | rgb(63, 76, 121) |
| HSL | hsl(227, 32%, 36%) |
| OKLCH | oklch(42.7% 0.077 270.7) |
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 #3F4C79 | 8.32:1 | AAA | Lc -93.3 | Preferred for body text |
| Black text on #3F4C79 | 2.52:1 | Fails | Lc 15.3 | Dividers and decoration only |
| #3F4C79 text on white | 8.32:1 | AAA | Lc 88.7 | Fine for body text |
| #3F4C79 text on black | 2.52:1 | Fails | Lc -13.5 | 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 800.
-
Step 50
50
#F4F5FA
oklch(97.1% 0.007 277.2)
-
Step 100
100
#E6EAF3
oklch(93.7% 0.013 266.7)
-
Step 200
200
#D3D9EA
oklch(88.6% 0.024 270.3)
-
Step 300
300
#B5C0DE
oklch(80.9% 0.044 269.5)
-
Step 400
400
#8F9FCE
oklch(70.7% 0.071 269.9)
-
Step 500
500
#7486C1
oklch(63% 0.092 270.6)
-
Step 600
600
#5D6FAE
oklch(55.5% 0.101 270.8)
-
Step 700
700
#4D5D95
oklch(49.1% 0.092 270.6)
-
Step 800
800 (this color)
#3F4C79
oklch(42.7% 0.077 270.7)
-
Step 900
900
#364062
oklch(37.8% 0.06 270.8)
-
Step 950
950
#1F2539
oklch(26.9% 0.038 270.9)
#3F4C79 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) | #3C517B | 0.015 |
| Deuteranopia (no green cones) | #364C78 | 0.012 |
| Tritanopia (no blue cones) | #2A555D | 0.067 |
| Achromatopsia (no color) | #4E4E4E | 0.077 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3F4C79
#3F4C79
oklch(42.7% 0.077 270.7)
- #5F4D14
#5F4D14
oklch(42.7% 0.077 90.7)
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 #3F4C79, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dusk #4E5481 ΔE 0.035
- Twilight #4E518B ΔE 0.040
- Dusk Blue #26538D ΔE 0.042
- Light Navy #155084 ΔE 0.043
- YInMn Blue #415A77 ΔE 0.044
- Light Navy Blue #2E5A88 ΔE 0.044
- Dusty Grape #545775 ΔE 0.050
- Deep Sea Blue #015482 ΔE 0.050
Use #3F4C79 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.