#166FB9
Closest named color: Mid Blue (#276AB3). oklch(53.2% 0.14 249.8), rgb(22, 111, 185).
Aa
White text reads best on this color (5.23:1).
About this color
#166FB9 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 53%, its chroma 0.140 and its hue 250°. Its hue sits on the cool side of the wheel. The nearest named color is Mid Blue (#276AB3), ΔE 0.016 away. White text reads best on it, at 5.23:1.
| Hue family | Blues |
| Lightness | medium-dark (53%) |
| Chroma | moderately saturated (0.140) |
| Temperature | cool |
| Nearest name | Mid Blue (#276AB3) |
| Black text | 4.00:1 |
| White text | 5.23:1 |
Values
| HEX | #166FB9 |
| RGB | rgb(22, 111, 185) |
| HSL | hsl(207, 79%, 41%) |
| OKLCH | oklch(53.2% 0.14 249.8) |
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 #166FB9 | 5.23:1 | AA | Lc -80.9 | Fine for body text |
| Black text on #166FB9 | 4.00:1 | AA large text | Lc 28.6 | Dividers and decoration only |
| #166FB9 text on white | 5.23:1 | AA | Lc 75.5 | Fine for body text |
| #166FB9 text on black | 4.00:1 | AA large text | Lc -26.2 | 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
#F1F6FB
oklch(97.1% 0.009 247.9)
-
Step 100
100
#E1EBF6
oklch(93.6% 0.018 250.6)
-
Step 200
200
#C8DCF0
oklch(88.6% 0.035 248.2)
-
Step 300
300
#A2C4E8
oklch(80.8% 0.063 250.1)
-
Step 400
400
#6EA5DD
oklch(70.6% 0.101 249.9)
-
Step 500
500
#458ED4
oklch(63.2% 0.129 249.7)
-
Step 600
600 (this color)
#166FB9
oklch(53.2% 0.14 249.8)
-
Step 700
700
#1163A7
oklch(49.1% 0.131 250)
-
Step 800
800
#135187
oklch(42.7% 0.108 249.9)
-
Step 900
900
#19446C
oklch(37.8% 0.083 249.6)
-
Step 950
950
#10283F
oklch(27% 0.053 249.5)
#166FB9 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) | #4A74BC | 0.043 |
| Deuteranopia (no green cones) | #3066B8 | 0.026 |
| Tritanopia (no blue cones) | #00818B | 0.101 |
| Achromatopsia (no color) | #6C6C6C | 0.140 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #166FB9
#166FB9
oklch(53.2% 0.14 249.8)
- #965E00
#965E00
oklch(53.1% 0.115 69.7)
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 #166FB9, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Mid Blue #276AB3 ΔE 0.016
- French Blue #436BAD ΔE 0.034
- Windows Blue #3778BF ΔE 0.036
- Nice Blue #107AB0 ΔE 0.037
- Flat Blue #3C73A8 ΔE 0.039
- Muted Blue #3B719F ΔE 0.048
- Ocean Blue #03719C ΔE 0.049
- Peacock Blue #016795 ΔE 0.060
Use #166FB9 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.