#42BACC
Closest named color: Turquoise Blue (#06B1C4). oklch(73% 0.107 209.2), rgb(66, 186, 204).
Aa
Black text reads best on this color (9.12:1).
About this color
#42BACC is a medium-light, moderately saturated teal or cyan. In OKLCH its lightness is 73%, its chroma 0.107 and its hue 209°. Its hue sits on the cool side of the wheel. The nearest named color is Turquoise Blue (#06B1C4), ΔE 0.036 away. Black text reads best on it, at 9.12:1.
| Hue family | Teals and cyans |
| Lightness | medium-light (73%) |
| Chroma | moderately saturated (0.107) |
| Temperature | cool |
| Nearest name | Turquoise Blue (#06B1C4) |
| Black text | 9.12:1 |
| White text | 2.30:1 |
Values
| HEX | #42BACC |
| RGB | rgb(66, 186, 204) |
| HSL | hsl(188, 58%, 53%) |
| OKLCH | oklch(73% 0.107 209.2) |
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 #42BACC | 2.30:1 | Fails | Lc -49.9 | Large or bold text, headings |
| Black text on #42BACC | 9.12:1 | AAA | Lc 58.9 | Large or bold text, headings |
| #42BACC text on white | 2.30:1 | Fails | Lc 45.0 | Large or bold text, headings |
| #42BACC text on black | 9.12:1 | AAA | Lc -57.1 | 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
#EFF7F9
oklch(97.1% 0.009 214.3)
-
Step 100
100
#DCEEF1
oklch(93.7% 0.019 208.8)
-
Step 200
200
#BEE0E6
oklch(88.4% 0.037 209.4)
-
Step 300
300
#8DCDD8
oklch(80.9% 0.067 209.4)
-
Step 400
400 (this color)
#42BACC
oklch(73% 0.107 209.2)
-
Step 500
500
#009BAD
oklch(63.1% 0.109 209.2)
-
Step 600
600
#008292
oklch(55.6% 0.096 209.8)
-
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)
#42BACC 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) | #AAB3CD | 0.102 |
| Deuteranopia (no green cones) | #96A5CC | 0.092 |
| Tritanopia (no blue cones) | #00C2BF | 0.039 |
| Achromatopsia (no color) | #ABABAB | 0.108 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #42BACC
#42BACC
oklch(73% 0.107 209.2)
- #E38D80
#E38D80
oklch(72.9% 0.107 29.2)
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 #42BACC, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Turquoise Blue #06B1C4 ΔE 0.036
- Topaz #13BBAF ΔE 0.050
- Dark Turquoise #00CED1 ΔE 0.055
- Light Sea Green #20B2AA ΔE 0.055
- Vivid Sky Blue #4CC9F0 ΔE 0.060
- Medium Turquoise #48D1CC ΔE 0.067
- Deep Sky Blue #00BFFF ΔE 0.073
- Greyblue #77A1B5 ΔE 0.074
Use #42BACC 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.