#42A7FF
Closest named color: Chefchaouen Blue (#4895EF). oklch(71% 0.159 248.5), rgb(66, 167, 255).
Aa
Black text reads best on this color (8.20:1).
About this color
#42A7FF is a medium-light, vivid blue. In OKLCH its lightness is 71%, its chroma 0.159 and its hue 249°. Its hue sits on the cool side of the wheel. The nearest named color is Chefchaouen Blue (#4895EF), ΔE 0.049 away. Black text reads best on it, at 8.20:1.
| Hue family | Blues |
| Lightness | medium-light (71%) |
| Chroma | vivid (0.159) |
| Temperature | cool |
| Nearest name | Chefchaouen Blue (#4895EF) |
| Black text | 8.20:1 |
| White text | 2.55:1 |
Values
| HEX | #42A7FF |
| RGB | rgb(66, 167, 255) |
| HSL | hsl(208, 100%, 63%) |
| OKLCH | oklch(71% 0.159 248.5) |
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 #42A7FF | 2.55:1 | Fails | Lc -54.8 | Large or bold text, headings |
| Black text on #42A7FF | 8.20:1 | AAA | Lc 54.3 | Large or bold text, headings |
| #42A7FF text on white | 2.55:1 | Fails | Lc 49.7 | Large or bold text, headings |
| #42A7FF text on black | 8.20:1 | AAA | Lc -52.2 | 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
#EFF6FE
oklch(97% 0.013 251.6)
-
Step 100
100
#DCECFD
oklch(93.6% 0.029 249.8)
-
Step 200
200
#BEDDFD
oklch(88.5% 0.055 249.3)
-
Step 300
300
#8DC6FE
oklch(80.8% 0.099 248.7)
-
Step 400
400 (this color)
#42A7FF
oklch(71% 0.159 248.5)
-
Step 500
500
#008DEB
oklch(63% 0.172 248.6)
-
Step 600
600
#0077C7
oklch(55.7% 0.152 248.5)
-
Step 700
700
#0064A8
oklch(49.2% 0.133 248.3)
-
Step 800
800
#00518B
oklch(42.6% 0.117 248.8)
-
Step 900
900
#004475
oklch(37.8% 0.103 248.3)
-
Step 950
950
#002848
oklch(27% 0.073 248.1)
#42A7FF 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) | #7EABFF | 0.055 |
| Deuteranopia (no green cones) | #639AFD | 0.039 |
| Tritanopia (no blue cones) | #00BCC7 | 0.116 |
| Achromatopsia (no color) | #A2A2A2 | 0.159 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #42A7FF
#42A7FF
oklch(71% 0.159 248.5)
- #DF8C00
#DF8C00
oklch(71% 0.155 68.5)
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 #42A7FF, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Chefchaouen Blue #4895EF ΔE 0.049
- Cornflower Blue #6495ED ΔE 0.052
- Deep Sky Blue #00BFFF ΔE 0.065
- Dodger Blue #1E90FF ΔE 0.067
- Dark Sky Blue #448EE4 ΔE 0.072
- Periwinkle Blue #8F99FB ΔE 0.078
- Soft Blue #6488EA ΔE 0.081
- Carolina Blue #8AB8FE ΔE 0.085
Use #42A7FF 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.