#42C8ED
Closest named color: Vivid Sky Blue (#4CC9F0). oklch(77.6% 0.124 220.4), rgb(66, 200, 237).
Aa
Black text reads best on this color (10.71:1).
About this color
#42C8ED is a medium-light, moderately saturated teal or cyan. In OKLCH its lightness is 78%, its chroma 0.124 and its hue 220°. Its hue sits on the cool side of the wheel. The nearest named color is Vivid Sky Blue (#4CC9F0), ΔE 0.008 away. Black text reads best on it, at 10.71:1.
| Hue family | Teals and cyans |
| Lightness | medium-light (78%) |
| Chroma | moderately saturated (0.124) |
| Temperature | cool |
| Nearest name | Vivid Sky Blue (#4CC9F0) |
| Black text | 10.71:1 |
| White text | 1.95:1 |
Values
| HEX | #42C8ED |
| RGB | rgb(66, 200, 237) |
| HSL | hsl(193, 83%, 59%) |
| OKLCH | oklch(77.6% 0.124 220.4) |
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 #42C8ED | 1.95:1 | Fails | Lc -41.7 | Non-text elements, placeholder text |
| Black text on #42C8ED | 10.71:1 | AAA | Lc 66.6 | Content text, not long reading |
| #42C8ED text on white | 1.95:1 | Fails | Lc 37.3 | Non-text elements, placeholder text |
| #42C8ED text on black | 10.71:1 | AAA | Lc -65.1 | 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
#EAF8FD
oklch(97% 0.016 221.1)
-
Step 100
100
#D1F0FB
oklch(93.6% 0.036 221.2)
-
Step 200
200
#A6E4F9
oklch(88.4% 0.069 220.9)
-
Step 300
300 (this color)
#42C8ED
oklch(77.6% 0.124 220.4)
-
Step 400
400
#00B2D8
oklch(70.7% 0.129 220.4)
-
Step 500
500
#0099BA
oklch(63.2% 0.115 220.3)
-
Step 600
600
#00809C
oklch(55.5% 0.101 220.3)
-
Step 700
700
#006C84
oklch(49.2% 0.09 220.2)
-
Step 800
800
#00586D
oklch(42.6% 0.078 221.3)
-
Step 900
900
#004A5B
oklch(37.8% 0.069 219.8)
-
Step 950
950
#002C37
oklch(27.1% 0.049 219.4)
#42C8ED 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) | #B2C3EF | 0.103 |
| Deuteranopia (no green cones) | #9AB2ED | 0.091 |
| Tritanopia (no blue cones) | #00D4D4 | 0.059 |
| Achromatopsia (no color) | #B9B9B9 | 0.124 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #42C8ED
#42C8ED
oklch(77.6% 0.124 220.4)
- #F99A78
#F99A78
oklch(77.6% 0.124 40.4)
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 #42C8ED, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Vivid Sky Blue #4CC9F0 ΔE 0.008
- Bright Sky Blue #02CCFE ΔE 0.026
- Lightblue #7BC8F6 ΔE 0.045
- Deep Sky Blue #00BFFF ΔE 0.045
- Aqua Blue #02D8E9 ΔE 0.047
- Dark Turquoise #00CED1 ΔE 0.053
- Sky #82CAFC ΔE 0.056
- Sky Blue #87CEEB ΔE 0.058
Use #42C8ED 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.