#3666CF#3666CF

#3666CF is a mid, vivid blue. Relative luminance 0.148; OKLCH L 53.6% C 0.171 H 263.3°. Best body text is #FFFFFF at 5.31:1 contrast (WCAG AA passes).

Color values

HEX	#3666CF
RGB	rgb(54, 102, 207)
HSL	hsl(221, 61%, 51%)
HSV	hsv(221, 74%, 81%)
CMYK	cmyk(73.9%, 50.7%, 0%, 18.8%)
CIE-LAB	lab(45.35, 20.20, -59.06)
CIE-LCH	lch(45.35, 62.42, 288.88°)
OKLab	oklab(53.58% -0.0199 -0.1699)
OKLCH	oklch(53.58% 0.171 263.3)
XYZ	xyz(17.5312, 14.7901, 60.9502)
Luminance	0.1479 (WCAG relative)
Temperature	cool
Family	blue

Closest named colors

Perceptual scales

Shades

Tints

Tones

OKLCH scale

Color harmonies

complementary

#3666CF #CF9F36

analogous

#36B3CF #3666CF #5236CF

triadic

#3666CF #CF3666 #66CF36

tetradic

#3666CF #CF36B3 #CF9F36 #36CF52

square

#3666CF #CF36B3 #CF9F36 #36CF52

split-complementary

#3666CF #CF5236 #B3CF36

monochromatic

#1B3570 #274DA1 #3666CF #678CDB #99B1E7

Accessibility & contrast

On white

5.31

#3666CF on #FFFFFF

AA ✓AA large ✓AAA ✗

On black

3.96

#3666CF on #000000

AA ✗AA large ✓AAA ✗

Best text color

#FFFFFF on #3666CF

5.31:1 — WCAG AA (normal text) passes

Contrast matrix

fg \ bg	##3666CF	#FFFFFF	#000000	##FFFFFF
##3666CF	1.00	5.31	3.96	5.31
#FFFFFF	5.31	1.00	21.00	1.00
#000000	3.96	21.00	1.00	21.00
##FFFFFF	5.31	1.00	21.00	1.00

Color blindness preview

Protanopia (red-blind)

#2473D3

Deuteranopia (green-blind)

#0065CD

Tritanopia (blue-blind)

#007F91

Achromatopsia (no color)

#6B6B6B

Design tokens & code

CSS

--color: #3666cf;
/* rgb */ color: rgb(54, 102, 207);
/* oklch */ color: oklch(53.6% 0.171 263.3);

Tailwind

colors: {
  custom: {
    50: '#8191de',
    500: '#3666cf',
    950: '#000000',
  },
}

SCSS

$custom: #3666cf;
$custom-light: #8191de;
$custom-dark: #000000;

JSON

{
  "hex": "#3666cf",
  "rgb": {
    "r": 54,
    "g": 102,
    "b": 207
  },
  "hsl": {
    "h": 221.176,
    "s": 61.446,
    "l": 51.176
  },
  "oklch": {
    "l": 0.53583,
    "c": 0.17103,
    "h": 263.3
  },
  "luminance": 0.14792
}

Semantic roles & 50–950 ramp

primary

#3666CF

secondary

#D2BD8F

accent

#B243E5

background

#F8F8FD

surface

#F0F0FB

border

#CBCBD4

text

#0C0C15

muted

#7D7D83

Preview Lab

Preview with #3666CF

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

Preview Lab → · Contrast checker → · Palette generator →