#166EA6
Closest named color: Ocean Blue (#03719C). oklch(51.8% 0.117 243.4), rgb(22, 110, 166).
Aa
White text reads best on this color (5.50:1).
About this color
#166EA6 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 52%, its chroma 0.117 and its hue 243°. Its hue sits on the cool side of the wheel. The nearest named color is Ocean Blue (#03719C), ΔE 0.021 away. White text reads best on it, at 5.50:1.
| Hue family | Blues |
| Lightness | medium-dark (52%) |
| Chroma | moderately saturated (0.117) |
| Temperature | cool |
| Nearest name | Ocean Blue (#03719C) |
| Black text | 3.81:1 |
| White text | 5.50:1 |
Values
| HEX | #166EA6 |
| RGB | rgb(22, 110, 166) |
| HSL | hsl(203, 77%, 37%) |
| OKLCH | oklch(51.8% 0.117 243.4) |
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 #166EA6 | 5.50:1 | AA | Lc -82.3 | Fine for body text |
| Black text on #166EA6 | 3.81:1 | AA large text | Lc 27.0 | Dividers and decoration only |
| #166EA6 text on white | 5.50:1 | AA | Lc 77.0 | Fine for body text |
| #166EA6 text on black | 3.81:1 | AA large text | Lc -24.7 | 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
#F1F6FA
oklch(97.1% 0.008 241.7)
-
Step 100
100
#E1EBF4
oklch(93.5% 0.016 245.1)
-
Step 200
200
#C8DCED
oklch(88.5% 0.032 243.7)
-
Step 300
300
#A2C6E3
oklch(81% 0.056 242.7)
-
Step 400
400
#6DA7D5
oklch(70.6% 0.091 243.5)
-
Step 500
500
#4290CA
oklch(63% 0.116 243.7)
-
Step 600
600
#197AB7
oklch(55.7% 0.126 243.1)
-
Step 700
700 (this color)
#166EA6
oklch(51.8% 0.117 243.4)
-
Step 800
800
#0E5380
oklch(42.6% 0.098 244)
-
Step 900
900
#164566
oklch(37.6% 0.076 243.3)
-
Step 950
950
#0F293C
oklch(27.1% 0.048 243)
#166EA6 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) | #5370A8 | 0.052 |
| Deuteranopia (no green cones) | #3F63A5 | 0.039 |
| Tritanopia (no blue cones) | #007C82 | 0.081 |
| Achromatopsia (no color) | #696969 | 0.118 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #166EA6
#166EA6
oklch(51.8% 0.117 243.4)
- #965701
#965701
oklch(51.8% 0.117 63.8)
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 #166EA6, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Ocean Blue #03719C ΔE 0.021
- Mid Blue #276AB3 ΔE 0.027
- Muted Blue #3B719F ΔE 0.029
- Flat Blue #3C73A8 ΔE 0.031
- Peacock Blue #016795 ΔE 0.033
- Nice Blue #107AB0 ΔE 0.035
- French Blue #436BAD ΔE 0.036
- Sea Blue #047495 ΔE 0.037
Use #166EA6 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.