#5F66B3
Closest named color: French Blue (#436BAD). oklch(54% 0.12 277.7), rgb(95, 102, 179).
Aa
White text reads best on this color (5.20:1).
About this color
#5F66B3 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 54%, its chroma 0.120 and its hue 278°. Its hue sits on the cool side of the wheel. The nearest named color is French Blue (#436BAD), ΔE 0.038 away. White text reads best on it, at 5.20:1.
| Hue family | Blues |
| Lightness | medium-dark (54%) |
| Chroma | moderately saturated (0.120) |
| Temperature | cool |
| Nearest name | French Blue (#436BAD) |
| Black text | 4.03:1 |
| White text | 5.20:1 |
Values
| HEX | #5F66B3 |
| RGB | rgb(95, 102, 179) |
| HSL | hsl(235, 36%, 54%) |
| OKLCH | oklch(54% 0.12 277.7) |
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 #5F66B3 | 5.20:1 | AA | Lc -81.0 | Fine for body text |
| Black text on #5F66B3 | 4.03:1 | AA large text | Lc 28.4 | Dividers and decoration only |
| #5F66B3 text on white | 5.20:1 | AA | Lc 75.7 | Fine for body text |
| #5F66B3 text on black | 4.03:1 | AA large text | Lc -26.1 | 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 600.
-
Step 50
50
#F4F5FA
oklch(97.1% 0.007 277.2)
-
Step 100
100
#E7E9F5
oklch(93.6% 0.016 278.5)
-
Step 200
200
#D4D8ED
oklch(88.6% 0.029 277.2)
-
Step 300
300
#B8BEE4
oklch(80.9% 0.054 278.1)
-
Step 400
400
#939CD6
oklch(70.7% 0.085 277.2)
-
Step 500
500
#7A82CB
oklch(63.1% 0.11 278)
-
Step 600
600 (this color)
#5F66B3
oklch(54% 0.12 277.7)
-
Step 700
700
#52599F
oklch(49.2% 0.111 277.2)
-
Step 800
800
#434981
oklch(42.8% 0.092 277.1)
-
Step 900
900
#393D67
oklch(37.7% 0.072 278.2)
-
Step 950
950
#21243C
oklch(27% 0.045 277.5)
#5F66B3 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) | #4870B6 | 0.036 |
| Deuteranopia (no green cones) | #416AB1 | 0.037 |
| Tritanopia (no blue cones) | #417684 | 0.105 |
| Achromatopsia (no color) | #6D6D6D | 0.120 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #5F66B3
#5F66B3
oklch(54% 0.12 277.7)
- #816E00
#816E00
oklch(54% 0.111 97.1)
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 #5F66B3, closest first.
No curated palette has a color within ΔE 0.04 of #5F66B3.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- French Blue #436BAD ΔE 0.038
- Iris #6258C4 ΔE 0.047
- Dark Periwinkle #665FD1 ΔE 0.053
- Slate Blue #6A5ACD ΔE 0.055
- Flat Blue #3C73A8 ΔE 0.057
- Mid Blue #276AB3 ΔE 0.058
- Light Indigo #6D5ACF ΔE 0.059
- Windows Blue #3778BF ΔE 0.060
Use #5F66B3 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.