#66BCDF
Closest named color: Vivid Sky Blue (#4CC9F0). oklch(75.5% 0.097 226.8), rgb(102, 188, 223).
Aa
Black text reads best on this color (9.82:1).
About this color
#66BCDF is a medium-light, moderately saturated teal or cyan. In OKLCH its lightness is 75%, its chroma 0.097 and its hue 227°. Its hue sits on the cool side of the wheel. The nearest named color is Vivid Sky Blue (#4CC9F0), ΔE 0.038 away. Black text reads best on it, at 9.82:1.
| Hue family | Teals and cyans |
| Lightness | medium-light (75%) |
| Chroma | moderately saturated (0.097) |
| Temperature | cool |
| Nearest name | Vivid Sky Blue (#4CC9F0) |
| Black text | 9.82:1 |
| White text | 2.13:1 |
Values
| HEX | #66BCDF |
| RGB | rgb(102, 188, 223) |
| HSL | hsl(197, 65%, 64%) |
| OKLCH | oklch(75.5% 0.097 226.8) |
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 #66BCDF | 2.13:1 | Fails | Lc -46.4 | Large or bold text, headings |
| Black text on #66BCDF | 9.82:1 | AAA | Lc 62.2 | Content text, not long reading |
| #66BCDF text on white | 2.13:1 | Fails | Lc 41.8 | Non-text elements, placeholder text |
| #66BCDF text on black | 9.82:1 | AAA | Lc -60.5 | 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 400.
-
Step 50
50
#F0F7FA
oklch(97.2% 0.008 225.1)
-
Step 100
100
#DEEDF3
oklch(93.7% 0.018 223.6)
-
Step 200
200
#C3DEEB
oklch(88.5% 0.034 228.4)
-
Step 300
300
#97C9DF
oklch(80.8% 0.061 226.8)
-
Step 400
400 (this color)
#66BCDF
oklch(75.5% 0.097 226.8)
-
Step 500
500
#0097C2
oklch(63.1% 0.122 226.9)
-
Step 600
600
#007FA3
oklch(55.6% 0.107 226.4)
-
Step 700
700
#006B8A
oklch(49.2% 0.095 226.5)
-
Step 800
800
#005772
oklch(42.6% 0.083 227.6)
-
Step 900
900
#00495F
oklch(37.8% 0.072 226.2)
-
Step 950
950
#012B3A
oklch(27% 0.052 227.6)
#66BCDF 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) | #A9B9E1 | 0.073 |
| Deuteranopia (no green cones) | #98ACDF | 0.064 |
| Tritanopia (no blue cones) | #00C6C7 | 0.068 |
| Achromatopsia (no color) | #B1B1B1 | 0.097 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #66BCDF
#66BCDF
oklch(75.5% 0.097 226.8)
- #E39C7A
#E39C7A
oklch(75.4% 0.097 46.4)
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 #66BCDF, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Vivid Sky Blue #4CC9F0 ΔE 0.038
- Lightblue #7BC8F6 ΔE 0.048
- Light Cornflower Blue #98C1D9 ΔE 0.055
- Deep Sky Blue #00BFFF ΔE 0.057
- Light Grey Blue #9DBCD4 ΔE 0.058
- Bright Sky Blue #02CCFE ΔE 0.059
- Sky #82CAFC ΔE 0.060
- Sky Blue #87CEEB ΔE 0.062
Use #66BCDF 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.