#3663EF
Closest named color: Neon Blue (#4361EE). oklch(55.5% 0.216 265.8), rgb(54, 99, 239).
Aa
White text reads best on this color (5.01:1).
About this color
#3663EF is a medium-dark, vivid blue. In OKLCH its lightness is 55%, its chroma 0.216 and its hue 266°. Its hue sits on the cool side of the wheel. The nearest named color is Neon Blue (#4361EE), ΔE 0.012 away. White text reads best on it, at 5.01:1.
| Hue family | Blues |
| Lightness | medium-dark (55%) |
| Chroma | vivid (0.216) |
| Temperature | cool |
| Nearest name | Neon Blue (#4361EE) |
| Black text | 4.18:1 |
| White text | 5.01:1 |
Values
| HEX | #3663EF |
| RGB | rgb(54, 99, 239) |
| HSL | hsl(225, 85%, 57%) |
| OKLCH | oklch(55.5% 0.216 265.8) |
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 #3663EF | 5.01:1 | AA | Lc -79.4 | Fine for body text |
| Black text on #3663EF | 4.18:1 | AA large text | Lc 30.1 | Non-text elements, placeholder text |
| #3663EF text on white | 5.01:1 | AA | Lc 74.0 | Content text, not long reading |
| #3663EF text on black | 4.18:1 | AA large text | Lc -27.7 | 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
#E1EAFD
oklch(93.6% 0.028 265.4)
-
Step 200
200
#C8D9FE
oklch(88.5% 0.054 265.8)
-
Step 300
300
#A4C0FF
oklch(81% 0.095 265.8)
-
Step 400
400
#739CFF
oklch(70.7% 0.152 265.7)
-
Step 500
500
#507FFF
oklch(63.1% 0.197 265.8)
-
Step 600
600 (this color)
#3663EF
oklch(55.5% 0.216 265.8)
-
Step 700
700
#2A51D0
oklch(49.1% 0.201 265.9)
-
Step 800
800
#2343A8
oklch(42.6% 0.167 265.9)
-
Step 900
900
#203A85
oklch(37.6% 0.13 265.9)
-
Step 950
950
#13234E
oklch(27% 0.082 265.8)
#3663EF 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) | #0078F4 | 0.050 |
| Deuteranopia (no green cones) | #0067EC | 0.025 |
| Tritanopia (no blue cones) | #00879F | 0.171 |
| Achromatopsia (no color) | #6F6F6F | 0.217 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3663EF
#3663EF
oklch(55.5% 0.216 265.8)
- #906D00
#906D00
oklch(55.4% 0.113 86.3)
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 #3663EF, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Neon Blue #4361EE ΔE 0.012
- Azul #1D5DEC ΔE 0.025
- Royal Blue #4169E1 ΔE 0.029
- Bright Blue #0165FC ΔE 0.030
- Cerulean Blue #056EEE ΔE 0.030
- Warm Blue #4B57DB ΔE 0.043
- Electric Blue #0652FF ΔE 0.054
- Clear Blue #247AFD ΔE 0.056
Use #3663EF 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.