#4F66C1
Closest named color: French Blue (#436BAD). oklch(53.9% 0.144 270.3), rgb(79, 102, 193).
Aa
White text reads best on this color (5.24:1).
About this color
#4F66C1 is a medium-dark, vivid blue. In OKLCH its lightness is 54%, its chroma 0.144 and its hue 270°. Its hue sits on the cool side of the wheel. The nearest named color is French Blue (#436BAD), ΔE 0.039 away. White text reads best on it, at 5.24:1.
| Hue family | Blues |
| Lightness | medium-dark (54%) |
| Chroma | vivid (0.144) |
| Temperature | cool |
| Nearest name | French Blue (#436BAD) |
| Black text | 4.00:1 |
| White text | 5.24:1 |
Values
| HEX | #4F66C1 |
| RGB | rgb(79, 102, 193) |
| HSL | hsl(228, 48%, 53%) |
| OKLCH | oklch(53.9% 0.144 270.3) |
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 #4F66C1 | 5.24:1 | AA | Lc -81.2 | Fine for body text |
| Black text on #4F66C1 | 4.00:1 | AA large text | Lc 28.3 | Dividers and decoration only |
| #4F66C1 text on white | 5.24:1 | AA | Lc 75.8 | Fine for body text |
| #4F66C1 text on black | 4.00:1 | AA large text | Lc -25.9 | 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 600.
-
Step 50
50
#F3F5FB
oklch(97% 0.008 271.3)
-
Step 100
100
#E5EAF7
oklch(93.7% 0.018 269.1)
-
Step 200
200
#D0D9F2
oklch(88.6% 0.036 269.9)
-
Step 300
300
#B0BFEB
oklch(80.8% 0.065 270.2)
-
Step 400
400
#889DE2
oklch(70.7% 0.104 270.6)
-
Step 500
500
#6B83D9
oklch(63% 0.133 270.5)
-
Step 600
600 (this color)
#4F66C1
oklch(53.9% 0.144 270.3)
-
Step 700
700
#4459AC
oklch(49.1% 0.134 270.2)
-
Step 800
800
#38498B
oklch(42.6% 0.111 270.3)
-
Step 900
900
#303E6F
oklch(37.7% 0.086 269.9)
-
Step 950
950
#1C2441
oklch(26.9% 0.055 270.7)
#4F66C1 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) | #3A71C4 | 0.033 |
| Deuteranopia (no green cones) | #2867BF | 0.038 |
| Tritanopia (no blue cones) | #007A8A | 0.126 |
| Achromatopsia (no color) | #6C6C6C | 0.144 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #4F66C1
#4F66C1
oklch(53.9% 0.144 270.3)
- #876A00
#876A00
oklch(53.8% 0.11 89.7)
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 #4F66C1, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- French Blue #436BAD ΔE 0.039
- Iris #6258C4 ΔE 0.041
- Dark Periwinkle #665FD1 ΔE 0.044
- Mid Blue #276AB3 ΔE 0.046
- Slate Blue #6A5ACD ΔE 0.050
- Royal Blue #4169E1 ΔE 0.050
- Windows Blue #3778BF ΔE 0.051
- Light Indigo #6D5ACF ΔE 0.055
Use #4F66C1 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.