#3666BF#3666BF

#3666BF is a mid, vivid blue. Relative luminance 0.140; OKLCH L 52.4% C 0.149 H 261.5°. Best body text is #FFFFFF at 5.51:1 contrast (WCAG AA passes).

Color values

HEX	#3666BF
RGB	rgb(54, 102, 191)
HSL	hsl(219, 56%, 48%)
HSV	hsv(219, 72%, 75%)
CMYK	cmyk(71.7%, 46.6%, 0%, 25.1%)
CIE-LAB	lab(44.30, 14.27, -51.52)
CIE-LCH	lch(44.30, 53.46, 285.48°)
OKLab	oklab(52.45% -0.0221 -0.1477)
OKLCH	oklch(52.45% 0.149 261.5)
XYZ	xyz(15.6733, 14.0469, 51.1654)
Luminance	0.1405 (WCAG relative)
Temperature	cool
Family	blue

Closest named colors

Perceptual scales

Shades

Tints

Tones

OKLCH scale

Color harmonies

complementary

#3666BF #BF8F36

analogous

#36AABF #3666BF #4A36BF

triadic

#3666BF #BF3666 #66BF36

tetradic

#3666BF #BF36AA #BF8F36 #36BF4A

square

#3666BF #BF36AA #BF8F36 #36BF4A

split-complementary

#3666BF #BF4A36 #AABF36

monochromatic

#1B3360 #294D8F #3666BF #6088D2 #90ACE0

Accessibility & contrast

On white

5.51

#3666BF on #FFFFFF

AA ✓AA large ✓AAA ✗

On black

3.81

#3666BF on #000000

AA ✗AA large ✓AAA ✗

Best text color

#FFFFFF on #3666BF

5.51:1 — WCAG AA (normal text) passes

Contrast matrix

fg \ bg	##3666BF	#FFFFFF	#000000	##FFFFFF
##3666BF	1.00	5.51	3.81	5.51
#FFFFFF	5.51	1.00	21.00	1.00
#000000	3.81	21.00	1.00	21.00
##FFFFFF	5.51	1.00	21.00	1.00

Color blindness preview

Protanopia (red-blind)

#376FC2

Deuteranopia (green-blind)

#1863BD

Tritanopia (blue-blind)

#007B89

Achromatopsia (no color)

#696969

Design tokens & code

CSS

--color: #3666bf;
/* rgb */ color: rgb(54, 102, 191);
/* oklch */ color: oklch(52.4% 0.149 261.5);

Tailwind

colors: {
  custom: {
    50: '#7e91d3',
    500: '#3666bf',
    950: '#000000',
  },
}

SCSS

$custom: #3666bf;
$custom-light: #7e91d3;
$custom-dark: #000000;

JSON

{
  "hex": "#3666bf",
  "rgb": {
    "r": 54,
    "g": 102,
    "b": 191
  },
  "hsl": {
    "h": 218.978,
    "s": 55.918,
    "l": 48.039
  },
  "oklch": {
    "l": 0.52449,
    "c": 0.14933,
    "h": 261.5
  },
  "luminance": 0.14049
}

Semantic roles & 50–950 ramp

primary

#3666BF

secondary

#CAB387

accent

#AA49DF

background

#F8F8FD

surface

#EFF0FA

border

#CACBD3

text

#0B0C14

muted

#7C7D83

Preview Lab

Preview with #3666BF

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

Preview Lab → · Contrast checker → · Palette generator →