#42CBFB
Closest named color: Vivid Sky Blue (#4CC9F0). oklch(78.9% 0.133 226.1), rgb(66, 203, 251).
Aa
Black text reads best on this color (11.16:1).
About this color
#42CBFB is a light, moderately saturated teal or cyan. In OKLCH its lightness is 79%, its chroma 0.133 and its hue 226°. Its hue sits on the cool side of the wheel. The nearest named color is Vivid Sky Blue (#4CC9F0), ΔE 0.015 away. Black text reads best on it, at 11.16:1.
| Hue family | Teals and cyans |
| Lightness | light (79%) |
| Chroma | moderately saturated (0.133) |
| Temperature | cool |
| Nearest name | Vivid Sky Blue (#4CC9F0) |
| Black text | 11.16:1 |
| White text | 1.88:1 |
Values
| HEX | #42CBFB |
| RGB | rgb(66, 203, 251) |
| HSL | hsl(196, 96%, 62%) |
| OKLCH | oklch(78.9% 0.133 226.1) |
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 #42CBFB | 1.88:1 | Fails | Lc -39.5 | Non-text elements, placeholder text |
| Black text on #42CBFB | 11.16:1 | AAA | Lc 68.6 | Content text, not long reading |
| #42CBFB text on white | 1.88:1 | Fails | Lc 35.3 | Non-text elements, placeholder text |
| #42CBFB text on black | 11.16:1 | AAA | Lc -67.3 | 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
#EAF8FF
oklch(97.1% 0.018 229)
-
Step 100
100
#D0F0FE
oklch(93.6% 0.038 226)
-
Step 200
200
#A5E4FF
oklch(88.6% 0.074 226.4)
-
Step 300
300 (this color)
#42CBFB
oklch(78.9% 0.133 226.1)
-
Step 400
400
#00B1E1
oklch(70.8% 0.135 226)
-
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)
#42CBFB 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) | #B1C7FD | 0.099 |
| Deuteranopia (no green cones) | #98B5FA | 0.087 |
| Tritanopia (no blue cones) | #00D9DB | 0.071 |
| Achromatopsia (no color) | #BDBDBD | 0.133 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #42CBFB
#42CBFB
oklch(78.9% 0.133 226.1)
- #FF9E70
#FF9E70
oklch(78.9% 0.131 45.7)
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 #42CBFB, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Vivid Sky Blue #4CC9F0 ΔE 0.015
- Bright Sky Blue #02CCFE ΔE 0.016
- Lightblue #7BC8F6 ΔE 0.040
- Deep Sky Blue #00BFFF ΔE 0.042
- Sky #82CAFC ΔE 0.047
- Aqua Blue #02D8E9 ΔE 0.052
- Light Sky Blue #87CEFA ΔE 0.054
- Sky Blue #87CEEB ΔE 0.057
Use #42CBFB 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.