#3F4B7F
Closest named color: Twilight (#4E518B). oklch(42.8% 0.088 272.4), rgb(63, 75, 127).
Aa
White text reads best on this color (8.31:1).
About this color
#3F4B7F is a dark, moderately saturated blue. In OKLCH its lightness is 43%, its chroma 0.088 and its hue 272°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight (#4E518B), ΔE 0.034 away. White text reads best on it, at 8.31:1.
| Hue family | Blues |
| Lightness | dark (43%) |
| Chroma | moderately saturated (0.088) |
| Temperature | cool |
| Nearest name | Twilight (#4E518B) |
| Black text | 2.52:1 |
| White text | 8.31:1 |
Values
| HEX | #3F4B7F |
| RGB | rgb(63, 75, 127) |
| HSL | hsl(229, 34%, 37%) |
| OKLCH | oklch(42.8% 0.088 272.4) |
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 #3F4B7F | 8.31:1 | AAA | Lc -93.2 | Preferred for body text |
| Black text on #3F4B7F | 2.52:1 | Fails | Lc 15.4 | Dividers and decoration only |
| #3F4B7F text on white | 8.31:1 | AAA | Lc 88.6 | Fine for body text |
| #3F4B7F text on black | 2.52:1 | Fails | Lc -13.6 | 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
#E6E9F4
oklch(93.5% 0.015 273.8)
-
Step 200
200
#D2D8ED
oklch(88.4% 0.03 273.1)
-
Step 300
300
#B5BFE3
oklch(80.9% 0.052 273)
-
Step 400
400
#8F9ED4
oklch(70.8% 0.081 272.2)
-
Step 500
500
#7485C9
oklch(63.2% 0.105 272.4)
-
Step 600
600
#5D6DB6
oklch(55.5% 0.115 272.8)
-
Step 700
700
#4D5B9C
oklch(49.1% 0.105 272.8)
-
Step 800
800 (this color)
#3F4B7F
oklch(42.8% 0.088 272.4)
-
Step 900
900
#353F66
oklch(37.8% 0.068 271.9)
-
Step 950
950
#1F253C
oklch(27% 0.044 272.1)
#3F4B7F 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) | #375181 | 0.019 |
| Deuteranopia (no green cones) | #314B7E | 0.018 |
| Tritanopia (no blue cones) | #26565F | 0.077 |
| Achromatopsia (no color) | #4E4E4E | 0.088 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3F4B7F
#3F4B7F
oklch(42.8% 0.088 272.4)
- #604D00
#604D00
oklch(42.7% 0.087 92.5)
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 #3F4B7F, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight #4E518B ΔE 0.034
- Dusk #4E5481 ΔE 0.036
- Dusk Blue #26538D ΔE 0.037
- Light Navy #155084 ΔE 0.042
- Light Navy Blue #2E5A88 ΔE 0.045
- Dark Slate Blue #483D8B ΔE 0.047
- Cobalt #1E488F ΔE 0.047
- Denim Blue #3B5B92 ΔE 0.050
Use #3F4B7F 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.