#0166A4
Closest named color: Peacock Blue (#016795). oklch(49.4% 0.126 245.8), rgb(1, 102, 164).
Aa
White text reads best on this color (6.10:1).
About this color
#0166A4 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 49%, its chroma 0.126 and its hue 246°. Its hue sits on the cool side of the wheel. The nearest named color is Peacock Blue (#016795), ΔE 0.025 away. White text reads best on it, at 6.10:1.
| Hue family | Blues |
| Lightness | medium-dark (49%) |
| Chroma | moderately saturated (0.126) |
| Temperature | cool |
| Nearest name | Peacock Blue (#016795) |
| Black text | 3.43:1 |
| White text | 6.10:1 |
Values
| HEX | #0166A4 |
| RGB | rgb(1, 102, 164) |
| HSL | hsl(203, 99%, 32%) |
| OKLCH | oklch(49.4% 0.126 245.8) |
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 #0166A4 | 6.10:1 | AA | Lc -85.1 | Fine for body text |
| Black text on #0166A4 | 3.43:1 | AA large text | Lc 24.2 | Dividers and decoration only |
| #0166A4 text on white | 6.10:1 | AA | Lc 79.9 | Fine for body text |
| #0166A4 text on black | 3.43:1 | AA large text | Lc -22.0 | 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
#F1F6FB
oklch(97.1% 0.009 247.9)
-
Step 100
100
#E1EBF5
oklch(93.5% 0.017 248)
-
Step 200
200
#C8DCEF
oklch(88.5% 0.034 246.8)
-
Step 300
300
#A1C5E6
oklch(80.8% 0.061 246.3)
-
Step 400
400
#6BA7DA
oklch(70.8% 0.098 245.4)
-
Step 500
500
#3F90D0
oklch(63.2% 0.125 245.5)
-
Step 600
600
#1478BD
oklch(55.5% 0.136 246.1)
-
Step 700
700 (this color)
#0166A4
oklch(49.4% 0.126 245.8)
-
Step 800
800
#0A5384
oklch(42.8% 0.104 245.6)
-
Step 900
900
#14456A
oklch(37.8% 0.082 245.5)
-
Step 950
950
#0E283E
oklch(26.9% 0.052 246.9)
#0166A4 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) | #4769A7 | 0.048 |
| Deuteranopia (no green cones) | #305CA3 | 0.033 |
| Tritanopia (no blue cones) | #00757D | 0.087 |
| Achromatopsia (no color) | #626262 | 0.126 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #0166A4
#0166A4
oklch(49.4% 0.126 245.8)
- #8B5200
#8B5200
oklch(49.3% 0.11 65.4)
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 #0166A4, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Peacock Blue #016795 ΔE 0.025
- Mid Blue #276AB3 ΔE 0.032
- Ocean Blue #03719C ΔE 0.038
- Denim Blue #3B5B92 ΔE 0.046
- Denim #3B638C ΔE 0.047
- French Blue #436BAD ΔE 0.048
- Dusky Blue #475F94 ΔE 0.050
- Muted Blue #3B719F ΔE 0.051
Use #0166A4 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.