#42B0BC
Closest named color: Turquoise Blue (#06B1C4). oklch(70% 0.099 205.3), rgb(66, 176, 188).
Aa
Black text reads best on this color (8.16:1).
About this color
#42B0BC is a medium-light, moderately saturated teal or cyan. In OKLCH its lightness is 70%, its chroma 0.099 and its hue 205°. Its hue sits on the cool side of the wheel. The nearest named color is Turquoise Blue (#06B1C4), ΔE 0.021 away. Black text reads best on it, at 8.16:1.
| Hue family | Teals and cyans |
| Lightness | medium-light (70%) |
| Chroma | moderately saturated (0.099) |
| Temperature | cool |
| Nearest name | Turquoise Blue (#06B1C4) |
| Black text | 8.16:1 |
| White text | 2.57:1 |
Values
| HEX | #42B0BC |
| RGB | rgb(66, 176, 188) |
| HSL | hsl(186, 48%, 50%) |
| OKLCH | oklch(70% 0.099 205.3) |
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 #42B0BC | 2.57:1 | Fails | Lc -55.1 | Large or bold text, headings |
| Black text on #42B0BC | 8.16:1 | AAA | Lc 54.0 | Large or bold text, headings |
| #42B0BC text on white | 2.57:1 | Fails | Lc 50.0 | Large or bold text, headings |
| #42B0BC text on black | 8.16:1 | AAA | Lc -51.9 | Large or bold text, headings |
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
#EFF7F8
oklch(97% 0.009 205.9)
-
Step 100
100
#DDEEF0
oklch(93.7% 0.018 205.3)
-
Step 200
200
#C0E0E4
oklch(88.5% 0.034 205.8)
-
Step 300
300
#91CDD4
oklch(81% 0.062 205.1)
-
Step 400
400 (this color)
#42B0BC
oklch(70% 0.099 205.3)
-
Step 500
500
#009CA9
oklch(63.2% 0.108 205.2)
-
Step 600
600
#00838E
oklch(55.7% 0.095 205.2)
-
Step 700
700
#006E77
oklch(49.1% 0.084 204.7)
-
Step 800
800
#005A62
oklch(42.7% 0.073 205.3)
-
Step 900
900
#004B52
oklch(37.7% 0.064 205.5)
-
Step 950
950
#002D31
oklch(27.1% 0.046 204.1)
#42B0BC 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) | #A2A9BD | 0.098 |
| Deuteranopia (no green cones) | #909CBC | 0.089 |
| Tritanopia (no blue cones) | #00B7B3 | 0.034 |
| Achromatopsia (no color) | #A1A1A1 | 0.100 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #42B0BC
#42B0BC
oklch(70% 0.099 205.3)
- #D5867F
#D5867F
oklch(70% 0.098 25.4)
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 #42B0BC, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Turquoise Blue #06B1C4 ΔE 0.021
- Light Sea Green #20B2AA ΔE 0.035
- Topaz #13BBAF ΔE 0.045
- Cadet Blue #5F9EA0 ΔE 0.055
- Greyblue #77A1B5 ΔE 0.056
- Greeny Blue #42B395 ΔE 0.062
- Bluegrey #85A3B2 ΔE 0.065
- Dull Teal #5F9E8F ΔE 0.069
Use #42B0BC 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.