#3F63AF
Closest named color: French Blue (#436BAD). oklch(51.1% 0.128 263.5), rgb(63, 99, 175).
Aa
White text reads best on this color (5.80:1).
About this color
#3F63AF is a medium-dark, moderately saturated blue. In OKLCH its lightness is 51%, its chroma 0.128 and its hue 263°. Its hue sits on the cool side of the wheel. The nearest named color is French Blue (#436BAD), ΔE 0.024 away. White text reads best on it, at 5.80:1.
| Hue family | Blues |
| Lightness | medium-dark (51%) |
| Chroma | moderately saturated (0.128) |
| Temperature | cool |
| Nearest name | French Blue (#436BAD) |
| Black text | 3.61:1 |
| White text | 5.80:1 |
Values
| HEX | #3F63AF |
| RGB | rgb(63, 99, 175) |
| HSL | hsl(221, 47%, 47%) |
| OKLCH | oklch(51.1% 0.128 263.5) |
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 #3F63AF | 5.80:1 | AA | Lc -84.1 | Fine for body text |
| Black text on #3F63AF | 3.61:1 | AA large text | Lc 25.2 | Dividers and decoration only |
| #3F63AF text on white | 5.80:1 | AA | Lc 78.8 | Fine for body text |
| #3F63AF text on black | 3.61:1 | AA large text | Lc -23.0 | 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
#F3F6FB
oklch(97.2% 0.007 260.7)
-
Step 100
100
#E4EAF6
oklch(93.6% 0.017 264.5)
-
Step 200
200
#CEDAF1
oklch(88.6% 0.034 263.6)
-
Step 300
300
#ACC1E9
oklch(80.9% 0.061 263.2)
-
Step 400
400
#80A0DF
oklch(70.7% 0.1 263.4)
-
Step 500
500
#6187D6
oklch(63.1% 0.127 263.7)
-
Step 600
600
#4870C3
oklch(55.7% 0.137 263.3)
-
Step 700
700 (this color)
#3F63AF
oklch(51.1% 0.128 263.5)
-
Step 800
800
#304C88
oklch(42.6% 0.105 263.7)
-
Step 900
900
#2A406D
oklch(37.7% 0.082 263.3)
-
Step 950
950
#192640
oklch(27.1% 0.052 263.2)
#3F63AF 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) | #406BB2 | 0.022 |
| Deuteranopia (no green cones) | #2F60AD | 0.019 |
| Tritanopia (no blue cones) | #007480 | 0.107 |
| Achromatopsia (no color) | #656565 | 0.128 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3F63AF
#3F63AF
oklch(51.1% 0.128 263.5)
- #836000
#836000
oklch(51.1% 0.105 83.6)
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 #3F63AF, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- French Blue #436BAD ΔE 0.024
- Mid Blue #276AB3 ΔE 0.025
- Dusky Blue #475F94 ΔE 0.043
- Flat Blue #3C73A8 ΔE 0.049
- Denim Blue #3B5B92 ΔE 0.049
- Muted Blue #3B719F ΔE 0.052
- Denim #3B638C ΔE 0.057
- Windows Blue #3778BF ΔE 0.059
Use #3F63AF 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.