#42AEFD
Closest named color: Deep Sky Blue (#00BFFF). oklch(72.4% 0.151 244.5), rgb(66, 174, 253).
Aa
Black text reads best on this color (8.70:1).
About this color
#42AEFD is a medium-light, vivid blue. In OKLCH its lightness is 72%, its chroma 0.151 and its hue 244°. Its hue sits on the cool side of the wheel. The nearest named color is Deep Sky Blue (#00BFFF), ΔE 0.046 away. Black text reads best on it, at 8.70:1.
| Hue family | Blues |
| Lightness | medium-light (72%) |
| Chroma | vivid (0.151) |
| Temperature | cool |
| Nearest name | Deep Sky Blue (#00BFFF) |
| Black text | 8.70:1 |
| White text | 2.41:1 |
Values
| HEX | #42AEFD |
| RGB | rgb(66, 174, 253) |
| HSL | hsl(205, 98%, 63%) |
| OKLCH | oklch(72.4% 0.151 244.5) |
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 #42AEFD | 2.41:1 | Fails | Lc -52.1 | Large or bold text, headings |
| Black text on #42AEFD | 8.70:1 | AAA | Lc 56.9 | Large or bold text, headings |
| #42AEFD text on white | 2.41:1 | Fails | Lc 47.1 | Large or bold text, headings |
| #42AEFD text on black | 8.70:1 | AAA | Lc -54.9 | 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
#EFF7FE
oklch(97.2% 0.013 244.3)
-
Step 100
100
#DBECFB
oklch(93.5% 0.027 244.7)
-
Step 200
200
#BDDEFA
oklch(88.6% 0.052 244)
-
Step 300
300
#8CC8F9
oklch(81% 0.093 243.9)
-
Step 400
400 (this color)
#42AEFD
oklch(72.4% 0.151 244.5)
-
Step 500
500
#0090E1
oklch(63.1% 0.158 244.7)
-
Step 600
600
#0079BE
oklch(55.6% 0.139 244.6)
-
Step 700
700
#0066A0
oklch(49.2% 0.121 244)
-
Step 800
800
#005385
oklch(42.7% 0.107 244.8)
-
Step 900
900
#00456F
oklch(37.6% 0.093 244.3)
-
Step 950
950
#002945
oklch(27.1% 0.068 244.5)
#42AEFD 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) | #8AB0FF | 0.066 |
| Deuteranopia (no green cones) | #6F9FFC | 0.049 |
| Tritanopia (no blue cones) | #00C1CA | 0.106 |
| Achromatopsia (no color) | #A7A7A7 | 0.151 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #42AEFD
#42AEFD
oklch(72.4% 0.151 244.5)
- #E68F28
#E68F28
oklch(72.5% 0.151 64.4)
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 #42AEFD, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Deep Sky Blue #00BFFF ΔE 0.046
- Chefchaouen Blue #4895EF ΔE 0.066
- Cornflower Blue #6495ED ΔE 0.066
- Carolina Blue #8AB8FE ΔE 0.073
- Bright Sky Blue #02CCFE ΔE 0.081
- Vivid Sky Blue #4CC9F0 ΔE 0.083
- Periwinkle Blue #8F99FB ΔE 0.085
- Dodger Blue #1E90FF ΔE 0.086
Use #42AEFD 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.