#3F4C8E
Closest named color: Twilight (#4E518B). oklch(44% 0.109 272.8), rgb(63, 76, 142).
Aa
White text reads best on this color (7.96:1).
About this color
#3F4C8E is a dark, moderately saturated blue. In OKLCH its lightness is 44%, its chroma 0.109 and its hue 273°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight (#4E518B), ΔE 0.028 away. White text reads best on it, at 7.96:1.
| Hue family | Blues |
| Lightness | dark (44%) |
| Chroma | moderately saturated (0.109) |
| Temperature | cool |
| Nearest name | Twilight (#4E518B) |
| Black text | 2.63:1 |
| White text | 7.96:1 |
Values
| HEX | #3F4C8E |
| RGB | rgb(63, 76, 142) |
| HSL | hsl(230, 39%, 40%) |
| OKLCH | oklch(44% 0.109 272.8) |
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 #3F4C8E | 7.96:1 | AAA | Lc -92.2 | Preferred for body text |
| Black text on #3F4C8E | 2.63:1 | Fails | Lc 16.6 | Dividers and decoration only |
| #3F4C8E text on white | 7.96:1 | AAA | Lc 87.5 | Fine for body text |
| #3F4C8E text on black | 2.63:1 | Fails | Lc -14.7 | 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
#F3F5FB
oklch(97% 0.008 271.3)
-
Step 100
100
#E5E9F7
oklch(93.5% 0.019 273.2)
-
Step 200
200
#D1D8F1
oklch(88.5% 0.035 273.2)
-
Step 300
300
#B2BFEB
oklch(81% 0.064 272)
-
Step 400
400
#8B9CE1
oklch(70.7% 0.103 272.9)
-
Step 500
500
#7082D8
oklch(63.1% 0.131 273.2)
-
Step 600
600
#596AC5
oklch(55.6% 0.142 273)
-
Step 700
700
#4958AA
oklch(49.1% 0.131 272.9)
-
Step 800
800 (this color)
#3F4C8E
oklch(44% 0.109 272.8)
-
Step 900
900
#333D6E
oklch(37.7% 0.085 273)
-
Step 950
950
#1E2441
oklch(27% 0.055 273.4)
#3F4C8E 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) | #2F5490 | 0.027 |
| Deuteranopia (no green cones) | #254E8D | 0.029 |
| Tritanopia (no blue cones) | #175A66 | 0.096 |
| Achromatopsia (no color) | #515151 | 0.109 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3F4C8E
#3F4C8E
oklch(44% 0.109 272.8)
- #645000
#645000
oklch(43.9% 0.09 92.1)
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 #3F4C8E, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight #4E518B ΔE 0.028
- Dusk Blue #26538D ΔE 0.032
- Blueberry #464196 ΔE 0.034
- Dark Slate Blue #483D8B ΔE 0.040
- Cobalt #1E488F ΔE 0.040
- Denim Blue #3B5B92 ΔE 0.042
- Dusk #4E5481 ΔE 0.042
- Light Navy Blue #2E5A88 ΔE 0.046
Use #3F4C8E 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.