#166AE0
Closest named color: Cerulean Blue (#056EEE). oklch(54.8% 0.196 258.8), rgb(22, 106, 224).
Aa
White text reads best on this color (5.03:1).
About this color
#166AE0 is a medium-dark, vivid blue. In OKLCH its lightness is 55%, its chroma 0.196 and its hue 259°. Its hue sits on the cool side of the wheel. The nearest named color is Cerulean Blue (#056EEE), ΔE 0.023 away. White text reads best on it, at 5.03:1.
| Hue family | Blues |
| Lightness | medium-dark (55%) |
| Chroma | vivid (0.196) |
| Temperature | cool |
| Nearest name | Cerulean Blue (#056EEE) |
| Black text | 4.17:1 |
| White text | 5.03:1 |
Values
| HEX | #166AE0 |
| RGB | rgb(22, 106, 224) |
| HSL | hsl(215, 82%, 48%) |
| OKLCH | oklch(54.8% 0.196 258.8) |
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 #166AE0 | 5.03:1 | AA | Lc -79.5 | Fine for body text |
| Black text on #166AE0 | 4.17:1 | AA large text | Lc 30.0 | Non-text elements, placeholder text |
| #166AE0 text on white | 5.03:1 | AA | Lc 74.1 | Content text, not long reading |
| #166AE0 text on black | 4.17:1 | AA large text | Lc -27.6 | 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 600.
-
Step 50
50
#F1F6FE
oklch(97.2% 0.012 259.8)
-
Step 100
100
#E0EBFB
oklch(93.7% 0.025 257.6)
-
Step 200
200
#C6DBFA
oklch(88.6% 0.048 258)
-
Step 300
300
#9EC2FA
oklch(80.8% 0.089 259.1)
-
Step 400
400
#69A1F7
oklch(70.8% 0.14 258.7)
-
Step 500
500
#3E86F4
oklch(63.1% 0.18 258.8)
-
Step 600
600 (this color)
#166AE0
oklch(54.8% 0.196 258.8)
-
Step 700
700
#095AC5
oklch(49.2% 0.182 258.7)
-
Step 800
800
#0E4A9F
oklch(42.7% 0.15 258.8)
-
Step 900
900
#153F7E
oklch(37.7% 0.117 258.8)
-
Step 950
950
#0D254A
oklch(26.9% 0.075 258.9)
#166AE0 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) | #0178E4 | 0.035 |
| Deuteranopia (no green cones) | #0067DE | 0.011 |
| Tritanopia (no blue cones) | #00879B | 0.147 |
| Achromatopsia (no color) | #6F6F6F | 0.196 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #166AE0
#166AE0
oklch(54.8% 0.196 258.8)
- #946800
#946800
oklch(54.9% 0.114 79.5)
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 #166AE0, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cerulean Blue #056EEE ΔE 0.023
- Royal Blue #4169E1 ΔE 0.029
- Azul #1D5DEC ΔE 0.036
- Neon Blue #4361EE ΔE 0.041
- Bright Blue #0165FC ΔE 0.045
- Warm Blue #4B57DB ΔE 0.055
- Clear Blue #247AFD ΔE 0.059
- Mid Blue #276AB3 ΔE 0.070
Use #166AE0 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.