#5166BE
Closest named color: French Blue (#436BAD). oklch(53.8% 0.139 271), rgb(81, 102, 190).
Aa
White text reads best on this color (5.25:1).
About this color
#5166BE is a medium-dark, moderately saturated blue. In OKLCH its lightness is 54%, its chroma 0.139 and its hue 271°. Its hue sits on the cool side of the wheel. The nearest named color is French Blue (#436BAD), ΔE 0.036 away. White text reads best on it, at 5.25:1.
| Hue family | Blues |
| Lightness | medium-dark (54%) |
| Chroma | moderately saturated (0.139) |
| Temperature | cool |
| Nearest name | French Blue (#436BAD) |
| Black text | 3.99:1 |
| White text | 5.25:1 |
Values
| HEX | #5166BE |
| RGB | rgb(81, 102, 190) |
| HSL | hsl(228, 46%, 53%) |
| OKLCH | oklch(53.8% 0.139 271) |
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 #5166BE | 5.25:1 | AA | Lc -81.3 | Fine for body text |
| Black text on #5166BE | 3.99:1 | AA large text | Lc 28.2 | Dividers and decoration only |
| #5166BE text on white | 5.25:1 | AA | Lc 75.9 | Fine for body text |
| #5166BE text on black | 3.99:1 | AA large text | Lc -25.8 | 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
#D0D8F1
oklch(88.4% 0.035 271.5)
-
Step 300
300
#B1BFEA
oklch(80.8% 0.063 270.8)
-
Step 400
400
#899DE0
oklch(70.7% 0.101 270.9)
-
Step 500
500
#6D83D7
oklch(63% 0.129 271.2)
-
Step 600
600 (this color)
#5166BE
oklch(53.8% 0.139 271)
-
Step 700
700
#4659A9
oklch(49% 0.129 270.9)
-
Step 800
800
#3A4989
oklch(42.6% 0.107 271.3)
-
Step 900
900
#313E6E
oklch(37.7% 0.084 270.5)
-
Step 950
950
#1D2440
oklch(26.9% 0.053 271.8)
#5166BE 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) | #3D71C1 | 0.033 |
| Deuteranopia (no green cones) | #2E67BC | 0.036 |
| Tritanopia (no blue cones) | #037A89 | 0.124 |
| Achromatopsia (no color) | #6C6C6C | 0.139 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #5166BE
#5166BE
oklch(53.8% 0.139 271)
- #866B00
#866B00
oklch(53.9% 0.11 91.3)
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 #5166BE, closest first.
No curated palette has a color within ΔE 0.04 of #5166BE.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- French Blue #436BAD ΔE 0.036
- Iris #6258C4 ΔE 0.042
- Dark Periwinkle #665FD1 ΔE 0.045
- Mid Blue #276AB3 ΔE 0.046
- Slate Blue #6A5ACD ΔE 0.051
- Windows Blue #3778BF ΔE 0.051
- Royal Blue #4169E1 ΔE 0.055
- Light Indigo #6D5ACF ΔE 0.055
Use #5166BE 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.