#66C8EE
Closest named color: Vivid Sky Blue (#4CC9F0). oklch(78.8% 0.107 226), rgb(102, 200, 238).
Aa
Black text reads best on this color (11.06:1).
About this color
#66C8EE is a light, moderately saturated teal or cyan. In OKLCH its lightness is 79%, its chroma 0.107 and its hue 226°. Its hue sits on the cool side of the wheel. The nearest named color is Vivid Sky Blue (#4CC9F0), ΔE 0.017 away. Black text reads best on it, at 11.06:1.
| Hue family | Teals and cyans |
| Lightness | light (79%) |
| Chroma | moderately saturated (0.107) |
| Temperature | cool |
| Nearest name | Vivid Sky Blue (#4CC9F0) |
| Black text | 11.06:1 |
| White text | 1.89:1 |
Values
| HEX | #66C8EE |
| RGB | rgb(102, 200, 238) |
| HSL | hsl(197, 80%, 67%) |
| OKLCH | oklch(78.8% 0.107 226) |
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 #66C8EE | 1.89:1 | Fails | Lc -40.2 | Non-text elements, placeholder text |
| Black text on #66C8EE | 11.06:1 | AAA | Lc 68.0 | Content text, not long reading |
| #66C8EE text on white | 1.89:1 | Fails | Lc 35.9 | Non-text elements, placeholder text |
| #66C8EE text on black | 11.06:1 | AAA | Lc -66.6 | Content text, not long reading |
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 300.
-
Step 50
50
#ECF8FD
oklch(97.2% 0.014 224.5)
-
Step 100
100
#D5EFFA
oklch(93.7% 0.031 225.1)
-
Step 200
200
#B0E2F7
oklch(88.5% 0.059 225.5)
-
Step 300
300 (this color)
#66C8EE
oklch(78.8% 0.107 226)
-
Step 400
400
#00B1E0
oklch(70.8% 0.135 225.5)
-
Step 500
500
#0097C1
oklch(63% 0.121 226.4)
-
Step 600
600
#007FA3
oklch(55.6% 0.107 226.4)
-
Step 700
700
#006B89
oklch(49.1% 0.094 225.7)
-
Step 800
800
#005771
oklch(42.6% 0.082 226.6)
-
Step 900
900
#00495F
oklch(37.8% 0.072 226.2)
-
Step 950
950
#002B3A
oklch(27% 0.052 227.2)
#66C8EE 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) | #B3C4F0 | 0.081 |
| Deuteranopia (no green cones) | #A0B6EE | 0.072 |
| Tritanopia (no blue cones) | #00D3D4 | 0.069 |
| Achromatopsia (no color) | #BCBCBC | 0.107 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #66C8EE
#66C8EE
oklch(78.8% 0.107 226)
- #F3A47F
#F3A47F
oklch(78.8% 0.107 45.8)
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 #66C8EE, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Vivid Sky Blue #4CC9F0 ΔE 0.017
- Lightblue #7BC8F6 ΔE 0.023
- Sky #82CAFC ΔE 0.034
- Sky Blue #87CEEB ΔE 0.036
- Light Sky Blue #87CEFA ΔE 0.040
- Bright Sky Blue #02CCFE ΔE 0.041
- Light Cornflower Blue #98C1D9 ΔE 0.052
- Aqua Blue #02D8E9 ΔE 0.056
Use #66C8EE 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.