#3F519E
Closest named color: Twilight (#4E518B). oklch(46.1% 0.126 270.8), rgb(63, 81, 158).
Aa
White text reads best on this color (7.28:1).
About this color
#3F519E is a medium-dark, moderately saturated blue. In OKLCH its lightness is 46%, its chroma 0.126 and its hue 271°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight (#4E518B), ΔE 0.037 away. White text reads best on it, at 7.28:1.
| Hue family | Blues |
| Lightness | medium-dark (46%) |
| Chroma | moderately saturated (0.126) |
| Temperature | cool |
| Nearest name | Twilight (#4E518B) |
| Black text | 2.88:1 |
| White text | 7.28:1 |
Values
| HEX | #3F519E |
| RGB | rgb(63, 81, 158) |
| HSL | hsl(229, 43%, 43%) |
| OKLCH | oklch(46.1% 0.126 270.8) |
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 #3F519E | 7.28:1 | AAA | Lc -90.0 | Fine for body text |
| Black text on #3F519E | 2.88:1 | Fails | Lc 18.9 | Dividers and decoration only |
| #3F519E text on white | 7.28:1 | AAA | Lc 85.1 | Fine for body text |
| #3F519E text on black | 2.88:1 | Fails | Lc -16.9 | Dividers and decoration only |
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 700.
-
Step 50
50
#F3F5FB
oklch(97% 0.008 271.3)
-
Step 100
100
#E5EAF6
oklch(93.7% 0.017 267.8)
-
Step 200
200
#D0D9F0
oklch(88.6% 0.033 268.7)
-
Step 300
300
#B2BFE9
oklch(80.9% 0.061 271.5)
-
Step 400
400
#8A9DDE
oklch(70.7% 0.098 271.2)
-
Step 500
500
#6E84D5
oklch(63.2% 0.125 271)
-
Step 600
600
#566CC2
oklch(55.6% 0.136 270.7)
-
Step 700
700 (this color)
#3F519E
oklch(46.1% 0.126 270.8)
-
Step 800
800
#3A4A88
oklch(42.8% 0.104 270.6)
-
Step 900
900
#323E6D
oklch(37.7% 0.082 271.2)
-
Step 950
950
#1D2540
oklch(27.1% 0.052 270.2)
#3F519E 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) | #2B5BA1 | 0.031 |
| Deuteranopia (no green cones) | #1B539C | 0.035 |
| Tritanopia (no blue cones) | #006270 | 0.110 |
| Achromatopsia (no color) | #565656 | 0.126 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3F519E
#3F519E
oklch(46.1% 0.126 270.8)
- #6C5500
#6C5500
oklch(46% 0.094 90.5)
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 #3F519E, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight #4E518B ΔE 0.037
- Denim Blue #3B5B92 ΔE 0.037
- Dusk Blue #26538D ΔE 0.041
- Blueberry #464196 ΔE 0.042
- Dusky Blue #475F94 ΔE 0.048
- Light Navy Blue #2E5A88 ΔE 0.051
- Cobalt #1E488F ΔE 0.053
- Dusk #4E5481 ΔE 0.054
Use #3F519E 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.