#166DAA
Closest named color: Mid Blue (#276AB3). oklch(51.8% 0.123 245.7), rgb(22, 109, 170).
Aa
White text reads best on this color (5.52:1).
About this color
#166DAA is a medium-dark, moderately saturated blue. In OKLCH its lightness is 52%, its chroma 0.123 and its hue 246°. Its hue sits on the cool side of the wheel. The nearest named color is Mid Blue (#276AB3), ΔE 0.020 away. White text reads best on it, at 5.52:1.
| Hue family | Blues |
| Lightness | medium-dark (52%) |
| Chroma | moderately saturated (0.123) |
| Temperature | cool |
| Nearest name | Mid Blue (#276AB3) |
| Black text | 3.80:1 |
| White text | 5.52:1 |
Values
| HEX | #166DAA |
| RGB | rgb(22, 109, 170) |
| HSL | hsl(205, 77%, 38%) |
| OKLCH | oklch(51.8% 0.123 245.7) |
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 #166DAA | 5.52:1 | AA | Lc -82.4 | Fine for body text |
| Black text on #166DAA | 3.80:1 | AA large text | Lc 27.0 | Dividers and decoration only |
| #166DAA text on white | 5.52:1 | AA | Lc 77.1 | Fine for body text |
| #166DAA text on black | 3.80:1 | AA large text | Lc -24.6 | 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
#C8DCEE
oklch(88.5% 0.033 245.3)
-
Step 300
300
#A1C5E5
oklch(80.8% 0.06 245.5)
-
Step 400
400
#6DA7D9
oklch(70.8% 0.095 245.7)
-
Step 500
500
#4190CE
oklch(63.2% 0.121 245.2)
-
Step 600
600
#1979BB
oklch(55.7% 0.132 245.3)
-
Step 700
700 (this color)
#166DAA
oklch(51.8% 0.123 245.7)
-
Step 800
800
#0E5383
oklch(42.8% 0.102 245.6)
-
Step 900
900
#164569
oklch(37.8% 0.079 245.5)
-
Step 950
950
#0F283D
oklch(26.8% 0.05 246.5)
#166DAA 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) | #5070AD | 0.049 |
| Deuteranopia (no green cones) | #3A63A9 | 0.034 |
| Tritanopia (no blue cones) | #007C83 | 0.087 |
| Achromatopsia (no color) | #696969 | 0.123 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #166DAA
#166DAA
oklch(51.8% 0.123 245.7)
- #945800
#945800
oklch(51.7% 0.115 65.7)
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 #166DAA, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Mid Blue #276AB3 ΔE 0.020
- Ocean Blue #03719C ΔE 0.028
- French Blue #436BAD ΔE 0.033
- Flat Blue #3C73A8 ΔE 0.033
- Muted Blue #3B719F ΔE 0.034
- Nice Blue #107AB0 ΔE 0.037
- Peacock Blue #016795 ΔE 0.037
- Sea Blue #047495 ΔE 0.044
Use #166DAA 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.