#3F9EFF
Closest named color: Chefchaouen Blue (#4895EF). oklch(68.9% 0.168 252), rgb(63, 158, 255).
Aa
Black text reads best on this color (7.54:1).
About this color
#3F9EFF is a medium-light, vivid blue. In OKLCH its lightness is 69%, its chroma 0.168 and its hue 252°. Its hue sits on the cool side of the wheel. The nearest named color is Chefchaouen Blue (#4895EF), ΔE 0.030 away. Black text reads best on it, at 7.54:1.
| Hue family | Blues |
| Lightness | medium-light (69%) |
| Chroma | vivid (0.168) |
| Temperature | cool |
| Nearest name | Chefchaouen Blue (#4895EF) |
| Black text | 7.54:1 |
| White text | 2.78:1 |
Values
| HEX | #3F9EFF |
| RGB | rgb(63, 158, 255) |
| HSL | hsl(210, 100%, 62%) |
| OKLCH | oklch(68.9% 0.168 252) |
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 #3F9EFF | 2.78:1 | Fails | Lc -58.5 | Large or bold text, headings |
| Black text on #3F9EFF | 7.54:1 | AAA | Lc 50.8 | Large or bold text, headings |
| #3F9EFF text on white | 2.78:1 | Fails | Lc 53.2 | Large or bold text, headings |
| #3F9EFF text on black | 7.54:1 | AAA | Lc -48.6 | 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
#EFF6FF
oklch(97% 0.014 254.6)
-
Step 100
100
#DCECFE
oklch(93.7% 0.03 251.3)
-
Step 200
200
#BEDCFF
oklch(88.4% 0.058 252.4)
-
Step 300
300
#92C5FF
oklch(80.9% 0.099 252.2)
-
Step 400
400 (this color)
#3F9EFF
oklch(68.9% 0.168 252)
-
Step 500
500
#008AF6
oklch(63% 0.189 252)
-
Step 600
600
#0074D0
oklch(55.6% 0.166 251.9)
-
Step 700
700
#0061B0
oklch(49% 0.147 252)
-
Step 800
800
#004F92
oklch(42.6% 0.129 252.3)
-
Step 900
900
#00427B
oklch(37.7% 0.113 252.1)
-
Step 950
950
#00274C
oklch(27.1% 0.08 251.6)
#3F9EFF 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) | #70A5FF | 0.048 |
| Deuteranopia (no green cones) | #5293FD | 0.029 |
| Tritanopia (no blue cones) | #00B5C2 | 0.126 |
| Achromatopsia (no color) | #9B9B9B | 0.168 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3F9EFF
#3F9EFF
oklch(68.9% 0.168 252)
- #D28900
#D28900
oklch(68.8% 0.147 71.9)
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 #3F9EFF, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Chefchaouen Blue #4895EF ΔE 0.030
- Cornflower Blue #6495ED ΔE 0.040
- Dodger Blue #1E90FF ΔE 0.044
- Dark Sky Blue #448EE4 ΔE 0.053
- Soft Blue #6488EA ΔE 0.062
- Periwinkle Blue #8F99FB ΔE 0.078
- Lavender Blue #8B88F8 ΔE 0.087
- Deep Sky Blue #00BFFF ΔE 0.088
Use #3F9EFF 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.