#3F97EB
Closest named color: Chefchaouen Blue (#4895EF). oklch(66.3% 0.151 250.3), rgb(63, 151, 235).
Aa
Black text reads best on this color (6.83:1).
About this color
#3F97EB is a medium-light, vivid blue. In OKLCH its lightness is 66%, its chroma 0.151 and its hue 250°. Its hue sits on the cool side of the wheel. The nearest named color is Chefchaouen Blue (#4895EF), ΔE 0.011 away. Black text reads best on it, at 6.83:1.
| Hue family | Blues |
| Lightness | medium-light (66%) |
| Chroma | vivid (0.151) |
| Temperature | cool |
| Nearest name | Chefchaouen Blue (#4895EF) |
| Black text | 6.83:1 |
| White text | 3.07:1 |
Values
| HEX | #3F97EB |
| RGB | rgb(63, 151, 235) |
| HSL | hsl(209, 81%, 58%) |
| OKLCH | oklch(66.3% 0.151 250.3) |
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 #3F97EB | 3.07:1 | AA large text | Lc -62.6 | Content text, not long reading |
| Black text on #3F97EB | 6.83:1 | AA | Lc 46.8 | Large or bold text, headings |
| #3F97EB text on white | 3.07:1 | AA large text | Lc 57.2 | Large or bold text, headings |
| #3F97EB text on black | 6.83:1 | AA | Lc -44.5 | Non-text elements, placeholder text |
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 500.
-
Step 50
50
#F1F6FC
oklch(97.1% 0.01 252.8)
-
Step 100
100
#E0EBF8
oklch(93.6% 0.021 252.5)
-
Step 200
200
#C6DCF4
oklch(88.6% 0.041 250.6)
-
Step 300
300
#9DC5EF
oklch(80.9% 0.073 250)
-
Step 400
400
#65A5E7
oklch(70.6% 0.118 250.5)
-
Step 500
500 (this color)
#3F97EB
oklch(66.3% 0.151 250.3)
-
Step 600
600
#0075CB
oklch(55.5% 0.159 250.4)
-
Step 700
700
#0062AC
oklch(49% 0.141 250.5)
-
Step 800
800
#00508E
oklch(42.6% 0.122 250.5)
-
Step 900
900
#0C4373
oklch(37.6% 0.098 250.3)
-
Step 950
950
#0A2843
oklch(27% 0.061 249.3)
#3F97EB 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) | #709CEE | 0.049 |
| Deuteranopia (no green cones) | #578CE9 | 0.032 |
| Tritanopia (no blue cones) | #00ABB6 | 0.112 |
| Achromatopsia (no color) | #939393 | 0.151 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3F97EB
#3F97EB
oklch(66.3% 0.151 250.3)
- #C98100
#C98100
oklch(66.2% 0.143 70.6)
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 #3F97EB, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Chefchaouen Blue #4895EF ΔE 0.011
- Dark Sky Blue #448EE4 ΔE 0.024
- Cornflower Blue #6495ED ΔE 0.032
- Dodger Blue #1E90FF ΔE 0.042
- Soft Blue #6488EA ΔE 0.047
- Water Blue #0E87CC ΔE 0.068
- Faded Blue #658CBB ΔE 0.075
- Cool Blue #4984B8 ΔE 0.083
Use #3F97EB 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.