#3666D3#3666D3

#3666D3 is a mid, vivid blue. Relative luminance 0.150; OKLCH L 53.9% C 0.176 H 263.7°. Best body text is #FFFFFF at 5.25:1 contrast (WCAG AA passes).

Color values

HEX	#3666D3
RGB	rgb(54, 102, 211)
HSL	hsl(222, 64%, 52%)
HSV	hsv(222, 74%, 83%)
CMYK	cmyk(74.4%, 51.7%, 0%, 17.3%)
CIE-LAB	lab(45.62, 21.68, -60.91)
CIE-LCH	lch(45.62, 64.65, 289.59°)
OKLab	oklab(53.88% -0.0195 -0.1753)
OKLCH	oklch(53.88% 0.176 263.7)
XYZ	xyz(18.0264, 14.9882, 63.5584)
Luminance	0.1499 (WCAG relative)
Temperature	cool
Family	blue

Closest named colors

Perceptual scales

Shades

Tints

Tones

OKLCH scale

Color harmonies

complementary

#3666D3 #D3A336

analogous

#36B5D3 #3666D3 #5536D3

triadic

#3666D3 #D33666 #66D336

tetradic

#3666D3 #D336B5 #D3A336 #36D355

square

#3666D3 #D336B5 #D3A336 #36D355

split-complementary

#3666D3 #D35536 #B5D336

monochromatic

#1A3675 #254DA7 #3666D3 #688CDE #9AB2E9

Accessibility & contrast

On white

5.25

#3666D3 on #FFFFFF

AA ✓AA large ✓AAA ✗

On black

4.00

#3666D3 on #000000

AA ✗AA large ✓AAA ✗

Best text color

#FFFFFF on #3666D3

5.25:1 — WCAG AA (normal text) passes

Contrast matrix

fg \ bg	##3666D3	#FFFFFF	#000000	##FFFFFF
##3666D3	1.00	5.25	4.00	5.25
#FFFFFF	5.25	1.00	21.00	1.00
#000000	4.00	21.00	1.00	21.00
##FFFFFF	5.25	1.00	21.00	1.00

Color blindness preview

Protanopia (red-blind)

#1D74D7

Deuteranopia (green-blind)

#0065D1

Tritanopia (blue-blind)

#008093

Achromatopsia (no color)

#6C6C6C

Design tokens & code

CSS

--color: #3666d3;
/* rgb */ color: rgb(54, 102, 211);
/* oklch */ color: oklch(53.9% 0.176 263.7);

Tailwind

colors: {
  custom: {
    50: '#8291e1',
    500: '#3666d3',
    950: '#000000',
  },
}

SCSS

$custom: #3666d3;
$custom-light: #8291e1;
$custom-dark: #000000;

JSON

{
  "hex": "#3666d3",
  "rgb": {
    "r": 54,
    "g": 102,
    "b": 211
  },
  "hsl": {
    "h": 221.656,
    "s": 64.082,
    "l": 51.961
  },
  "oklch": {
    "l": 0.53877,
    "c": 0.17638,
    "h": 263.7
  },
  "luminance": 0.1499
}

Semantic roles & 50–950 ramp

primary

#3666D3

secondary

#D5C090

accent

#B441E7

background

#F8F8FD

surface

#F0F0FB

border

#CBCBD4

text

#0C0C15

muted

#7D7D83

Preview Lab

Preview with #3666D3

Body copy rendered with the generated semantic roles for this colour.

Preview Lab → · Contrast checker → · Palette generator →