#42B2FE
Closest named color: Deep Sky Blue (#00BFFF). oklch(73.4% 0.149 242.7), rgb(66, 178, 254).
Aa
Black text reads best on this color (9.03:1).
About this color
#42B2FE is a medium-light, vivid blue. In OKLCH its lightness is 73%, its chroma 0.149 and its hue 243°. Its hue sits on the cool side of the wheel. The nearest named color is Deep Sky Blue (#00BFFF), ΔE 0.036 away. Black text reads best on it, at 9.03:1.
| Hue family | Blues |
| Lightness | medium-light (73%) |
| Chroma | vivid (0.149) |
| Temperature | cool |
| Nearest name | Deep Sky Blue (#00BFFF) |
| Black text | 9.03:1 |
| White text | 2.32:1 |
Values
| HEX | #42B2FE |
| RGB | rgb(66, 178, 254) |
| HSL | hsl(204, 99%, 63%) |
| OKLCH | oklch(73.4% 0.149 242.7) |
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 #42B2FE | 2.32:1 | Fails | Lc -50.4 | Large or bold text, headings |
| Black text on #42B2FE | 9.03:1 | AAA | Lc 58.5 | Large or bold text, headings |
| #42B2FE text on white | 2.32:1 | Fails | Lc 45.5 | Large or bold text, headings |
| #42B2FE text on black | 9.03:1 | AAA | Lc -56.6 | 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
#EFF7FD
oklch(97.2% 0.012 239.9)
-
Step 100
100
#DBEDFB
oklch(93.7% 0.027 241.2)
-
Step 200
200
#BCDEF9
oklch(88.5% 0.052 242.2)
-
Step 300
300
#8BC8F8
oklch(80.9% 0.093 243)
-
Step 400
400 (this color)
#42B2FE
oklch(73.4% 0.149 242.7)
-
Step 500
500
#0091DD
oklch(63.1% 0.152 242.9)
-
Step 600
600
#007ABA
oklch(55.6% 0.133 242.5)
-
Step 700
700
#00669E
oklch(49% 0.119 243.2)
-
Step 800
800
#005482
oklch(42.8% 0.102 242.4)
-
Step 900
900
#00466D
oklch(37.8% 0.09 242.2)
-
Step 950
950
#002943
oklch(27% 0.065 242.6)
#42B2FE 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) | #8FB4FF | 0.070 |
| Deuteranopia (no green cones) | #75A2FD | 0.054 |
| Tritanopia (no blue cones) | #00C5CD | 0.103 |
| Achromatopsia (no color) | #AAAAAA | 0.149 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #42B2FE
#42B2FE
oklch(73.4% 0.149 242.7)
- #EA9133
#EA9133
oklch(73.4% 0.149 62.4)
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 #42B2FE, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Deep Sky Blue #00BFFF ΔE 0.036
- Carolina Blue #8AB8FE ΔE 0.067
- Bright Sky Blue #02CCFE ΔE 0.071
- Vivid Sky Blue #4CC9F0 ΔE 0.073
- Cornflower Blue #6495ED ΔE 0.076
- Chefchaouen Blue #4895EF ΔE 0.077
- Lightblue #7BC8F6 ΔE 0.083
- Periwinkle Blue #8F99FB ΔE 0.089
Use #42B2FE 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.