#4F66B9
Closest named color: French Blue (#436BAD). oklch(53.3% 0.133 269.8), rgb(79, 102, 185).
Aa
White text reads best on this color (5.33:1).
About this color
#4F66B9 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 53%, its chroma 0.133 and its hue 270°. Its hue sits on the cool side of the wheel. The nearest named color is French Blue (#436BAD), ΔE 0.029 away. White text reads best on it, at 5.33:1.
| Hue family | Blues |
| Lightness | medium-dark (53%) |
| Chroma | moderately saturated (0.133) |
| Temperature | cool |
| Nearest name | French Blue (#436BAD) |
| Black text | 3.93:1 |
| White text | 5.33:1 |
Values
| HEX | #4F66B9 |
| RGB | rgb(79, 102, 185) |
| HSL | hsl(227, 43%, 52%) |
| OKLCH | oklch(53.3% 0.133 269.8) |
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 #4F66B9 | 5.33:1 | AA | Lc -81.7 | Fine for body text |
| Black text on #4F66B9 | 3.93:1 | AA large text | Lc 27.7 | Dividers and decoration only |
| #4F66B9 text on white | 5.33:1 | AA | Lc 76.4 | Fine for body text |
| #4F66B9 text on black | 3.93:1 | AA large text | Lc -25.4 | 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
#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
#B1C0E8
oklch(81% 0.059 268.9)
-
Step 400
400
#899EDD
oklch(70.7% 0.096 269.7)
-
Step 500
500
#6D85D3
oklch(63.2% 0.121 269.8)
-
Step 600
600 (this color)
#4F66B9
oklch(53.3% 0.133 269.8)
-
Step 700
700
#465AA6
oklch(49% 0.124 270.2)
-
Step 800
800
#394A87
oklch(42.7% 0.103 269.9)
-
Step 900
900
#313E6C
oklch(37.6% 0.081 270.3)
-
Step 950
950
#1D253F
oklch(27.1% 0.05 269.9)
#4F66B9 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) | #4170BC | 0.028 |
| Deuteranopia (no green cones) | #3267B7 | 0.030 |
| Tritanopia (no blue cones) | #047886 | 0.119 |
| Achromatopsia (no color) | #6B6B6B | 0.133 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #4F66B9
#4F66B9
oklch(53.3% 0.133 269.8)
- #856900
#856900
oklch(53.3% 0.109 90.3)
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 #4F66B9, closest first.
No curated palette has a color within ΔE 0.04 of #4F66B9.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- French Blue #436BAD ΔE 0.029
- Mid Blue #276AB3 ΔE 0.040
- Iris #6258C4 ΔE 0.047
- Windows Blue #3778BF ΔE 0.050
- Flat Blue #3C73A8 ΔE 0.052
- Dark Periwinkle #665FD1 ΔE 0.053
- Slate Blue #6A5ACD ΔE 0.057
- Muted Blue #3B719F ΔE 0.060
Use #4F66B9 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.