#3F658B
Closest named color: Denim (#3B638C). oklch(49.5% 0.075 249.6), rgb(63, 101, 139).
Aa
White text reads best on this color (6.09:1).
About this color
#3F658B is a medium-dark, moderately saturated blue. In OKLCH its lightness is 50%, its chroma 0.075 and its hue 250°. Its hue sits on the cool side of the wheel. The nearest named color is Denim (#3B638C), ΔE 0.008 away. White text reads best on it, at 6.09:1.
| Hue family | Blues |
| Lightness | medium-dark (50%) |
| Chroma | moderately saturated (0.075) |
| Temperature | cool |
| Nearest name | Denim (#3B638C) |
| Black text | 3.44:1 |
| White text | 6.09:1 |
Values
| HEX | #3F658B |
| RGB | rgb(63, 101, 139) |
| HSL | hsl(210, 38%, 40%) |
| OKLCH | oklch(49.5% 0.075 249.6) |
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 #3F658B | 6.09:1 | AA | Lc -85.5 | Fine for body text |
| Black text on #3F658B | 3.44:1 | AA large text | Lc 23.7 | Dividers and decoration only |
| #3F658B text on white | 6.09:1 | AA | Lc 80.3 | Fine for body text |
| #3F658B text on black | 3.44:1 | AA large text | Lc -21.5 | 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
#F3F6F9
oklch(97.2% 0.005 247.9)
-
Step 100
100
#E5EBF1
oklch(93.7% 0.01 247.9)
-
Step 200
200
#CFDBE6
oklch(88.6% 0.02 245.7)
-
Step 300
300
#AFC3D8
oklch(80.9% 0.037 249.6)
-
Step 400
400
#85A4C4
oklch(70.7% 0.058 249.5)
-
Step 500
500
#668DB5
oklch(63% 0.075 249.7)
-
Step 600
600
#4D77A1
oklch(55.6% 0.081 249.5)
-
Step 700
700 (this color)
#3F658B
oklch(49.5% 0.075 249.6)
-
Step 800
800
#335270
oklch(42.8% 0.062 248.7)
-
Step 900
900
#2D445A
oklch(37.8% 0.048 248.1)
-
Step 950
950
#1B2835
oklch(27.1% 0.03 249)
#3F658B 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) | #55668D | 0.028 |
| Deuteranopia (no green cones) | #4C5F8A | 0.022 |
| Tritanopia (no blue cones) | #126E72 | 0.065 |
| Achromatopsia (no color) | #626262 | 0.075 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3F658B
#3F658B
oklch(49.5% 0.075 249.6)
- #7D5A2F
#7D5A2F
oklch(49.5% 0.075 70.2)
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 #3F658B, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Denim #3B638C ΔE 0.008
- Dusky Blue #475F94 ΔE 0.027
- Denim Blue #3B5B92 ΔE 0.035
- Peacock Blue #016795 ΔE 0.038
- Light Navy Blue #2E5A88 ΔE 0.040
- YInMn Blue #415A77 ΔE 0.040
- Muted Blue #3B719F ΔE 0.041
- Slate #516572 ΔE 0.045
Use #3F658B 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.