#3666CC#3666CC

#3666CC is a mid, vivid blue. Relative luminance 0.146; OKLCH L 53.4% C 0.167 H 263.0°. Best body text is #FFFFFF at 5.34:1 contrast (WCAG AA passes).

Color values

HEX	#3666CC
RGB	rgb(54, 102, 204)
HSL	hsl(221, 60%, 51%)
HSV	hsv(221, 74%, 80%)
CMYK	cmyk(73.5%, 50%, 0%, 20%)
CIE-LAB	lab(45.14, 19.09, -57.67)
CIE-LCH	lch(45.14, 60.74, 288.31°)
OKLab	oklab(53.36% -0.0203 -0.1657)
OKLCH	oklch(53.36% 0.167 263)
XYZ	xyz(17.1679, 14.6448, 59.0370)
Luminance	0.1465 (WCAG relative)
Temperature	cool
Family	blue

Closest named colors

Perceptual scales

Shades

Tints

Tones

OKLCH scale

Color harmonies

complementary

#3666CC #CC9C36

analogous

#36B1CC #3666CC #5136CC

triadic

#3666CC #CC3666 #66CC36

tetradic

#3666CC #CC36B1 #CC9C36 #36CC51

square

#3666CC #CC36B1 #CC9C36 #36CC51

split-complementary

#3666CC #CC5136 #B1CC36

monochromatic

#1B356C #284D9D #3666CC #678BD8 #98B0E5

Accessibility & contrast

On white

5.34

#3666CC on #FFFFFF

AA ✓AA large ✓AAA ✗

On black

3.93

#3666CC on #000000

AA ✗AA large ✓AAA ✗

Best text color

#FFFFFF on #3666CC

5.34:1 — WCAG AA (normal text) passes

Contrast matrix

fg \ bg	##3666CC	#FFFFFF	#000000	##FFFFFF
##3666CC	1.00	5.34	3.93	5.34
#FFFFFF	5.34	1.00	21.00	1.00
#000000	3.93	21.00	1.00	21.00
##FFFFFF	5.34	1.00	21.00	1.00

Color blindness preview

Protanopia (red-blind)

#2972D0

Deuteranopia (green-blind)

#0064CA

Tritanopia (blue-blind)

#007E8F

Achromatopsia (no color)

#6B6B6B

Design tokens & code

CSS

--color: #3666cc;
/* rgb */ color: rgb(54, 102, 204);
/* oklch */ color: oklch(53.4% 0.167 263.0);

Tailwind

colors: {
  custom: {
    50: '#8191dc',
    500: '#3666cc',
    950: '#000000',
  },
}

SCSS

$custom: #3666cc;
$custom-light: #8191dc;
$custom-dark: #000000;

JSON

{
  "hex": "#3666cc",
  "rgb": {
    "r": 54,
    "g": 102,
    "b": 204
  },
  "hsl": {
    "h": 220.8,
    "s": 59.524,
    "l": 50.588
  },
  "oklch": {
    "l": 0.53365,
    "c": 0.16699,
    "h": 263
  },
  "luminance": 0.14647
}

Semantic roles & 50–950 ramp

primary

#3666CC

secondary

#D0BB8E

accent

#B045E3

background

#F8F8FD

surface

#F0F0FB

border

#CBCBD4

text

#0C0C15

muted

#7D7D83

Preview Lab

Preview with #3666CC

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

Preview Lab → · Contrast checker → · Palette generator →