#42CBDF
Closest named color: Vivid Sky Blue (#4CC9F0). oklch(77.8% 0.117 209.1), rgb(66, 203, 223).
Aa
Black text reads best on this color (10.83:1).
About this color
#42CBDF is a medium-light, moderately saturated teal or cyan. In OKLCH its lightness is 78%, its chroma 0.117 and its hue 209°. Its hue sits on the cool side of the wheel. The nearest named color is Vivid Sky Blue (#4CC9F0), ΔE 0.028 away. Black text reads best on it, at 10.83:1.
| Hue family | Teals and cyans |
| Lightness | medium-light (78%) |
| Chroma | moderately saturated (0.117) |
| Temperature | cool |
| Nearest name | Vivid Sky Blue (#4CC9F0) |
| Black text | 10.83:1 |
| White text | 1.93:1 |
Values
| HEX | #42CBDF |
| RGB | rgb(66, 203, 223) |
| HSL | hsl(188, 71%, 57%) |
| OKLCH | oklch(77.8% 0.117 209.1) |
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 #42CBDF | 1.93:1 | Fails | Lc -41.1 | Non-text elements, placeholder text |
| Black text on #42CBDF | 10.83:1 | AAA | Lc 67.1 | Content text, not long reading |
| #42CBDF text on white | 1.93:1 | Fails | Lc 36.8 | Non-text elements, placeholder text |
| #42CBDF text on black | 10.83:1 | AAA | Lc -65.7 | 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
#EAF9FB
oklch(97.2% 0.016 206.4)
-
Step 100
100
#D1F1F6
oklch(93.7% 0.034 208)
-
Step 200
200
#A6E6F0
oklch(88.5% 0.066 208.1)
-
Step 300
300 (this color)
#42CBDF
oklch(77.8% 0.117 209.1)
-
Step 400
400
#00B5C9
oklch(70.8% 0.122 208.7)
-
Step 500
500
#009BAD
oklch(63.1% 0.109 209.2)
-
Step 600
600
#008291
oklch(55.5% 0.096 208.9)
-
Step 700
700
#006D7B
oklch(49% 0.085 210.2)
-
Step 800
800
#005A65
oklch(42.8% 0.074 209.1)
-
Step 900
900
#004B54
oklch(37.8% 0.065 208.5)
-
Step 950
950
#002C33
oklch(26.9% 0.047 211.1)
#42CBDF 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) | #B9C4E0 | 0.111 |
| Deuteranopia (no green cones) | #A3B3DF | 0.102 |
| Tritanopia (no blue cones) | #00D4D1 | 0.040 |
| Achromatopsia (no color) | #BABABA | 0.118 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #42CBDF
#42CBDF
oklch(77.8% 0.117 209.1)
- #F9998B
#F9998B
oklch(77.8% 0.118 28.9)
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 #42CBDF, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Vivid Sky Blue #4CC9F0 ΔE 0.028
- Dark Turquoise #00CED1 ΔE 0.031
- Aqua Blue #02D8E9 ΔE 0.035
- Medium Turquoise #48D1CC ΔE 0.037
- Bright Sky Blue #02CCFE ΔE 0.045
- Lightblue #7BC8F6 ΔE 0.058
- Sky Blue #87CEEB ΔE 0.059
- Deep Sky Blue #00BFFF ΔE 0.067
Use #42CBDF 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.