#3966FB
Closest named color: Neon Blue (#4361EE). oklch(57.1% 0.227 266.2), rgb(57, 102, 251).
Aa
White text reads best on this color (4.70:1).
About this color
#3966FB is a medium-dark, vivid blue. In OKLCH its lightness is 57%, its chroma 0.227 and its hue 266°. Its hue sits on the cool side of the wheel. The nearest named color is Neon Blue (#4361EE), ΔE 0.023 away. White text reads best on it, at 4.70:1.
| Hue family | Blues |
| Lightness | medium-dark (57%) |
| Chroma | vivid (0.227) |
| Temperature | cool |
| Nearest name | Neon Blue (#4361EE) |
| Black text | 4.46:1 |
| White text | 4.70:1 |
Values
| HEX | #3966FB |
| RGB | rgb(57, 102, 251) |
| HSL | hsl(226, 96%, 60%) |
| OKLCH | oklch(57.1% 0.227 266.2) |
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 #3966FB | 4.70:1 | AA | Lc -77.4 | Fine for body text |
| Black text on #3966FB | 4.46:1 | AA large text | Lc 32.1 | Non-text elements, placeholder text |
| #3966FB text on white | 4.70:1 | AA | Lc 72.0 | Content text, not long reading |
| #3966FB text on black | 4.46:1 | AA large text | Lc -29.7 | Dividers and decoration only |
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 600.
-
Step 50
50
#F1F5FF
oklch(97% 0.014 268.5)
-
Step 100
100
#E1EAFE
oklch(93.6% 0.029 266.4)
-
Step 200
200
#C8D9FF
oklch(88.5% 0.056 266.2)
-
Step 300
300
#A4C0FF
oklch(81% 0.095 265.8)
-
Step 400
400
#749CFF
oklch(70.8% 0.152 266)
-
Step 500
500
#517FFF
oklch(63.2% 0.197 266)
-
Step 600
600 (this color)
#3966FB
oklch(57.1% 0.227 266.2)
-
Step 700
700
#294FD6
oklch(49.2% 0.211 266.2)
-
Step 800
800
#2242AD
oklch(42.8% 0.175 266.1)
-
Step 900
900
#1F3989
oklch(37.7% 0.137 266.2)
-
Step 950
950
#122250
oklch(26.9% 0.087 266.2)
#3966FB 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) | #007DFF | 0.054 |
| Deuteranopia (no green cones) | #006BF8 | 0.027 |
| Tritanopia (no blue cones) | #008CA7 | 0.177 |
| Achromatopsia (no color) | #747474 | 0.228 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3966FB
#3966FB
oklch(57.1% 0.227 266.2)
- #967200
#967200
oklch(57.2% 0.117 86.5)
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 #3966FB, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Neon Blue #4361EE ΔE 0.023
- Bright Blue #0165FC ΔE 0.027
- Cerulean Blue #056EEE ΔE 0.035
- Azul #1D5DEC ΔE 0.040
- Royal Blue #4169E1 ΔE 0.041
- Clear Blue #247AFD ΔE 0.046
- Electric Blue #0652FF ΔE 0.057
- Warm Blue #4B57DB ΔE 0.059
Use #3966FB 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.