#3F66CC#3F66CC

#3F66CC is a mid, vivid blue. Relative luminance 0.149; OKLCH L 53.8% C 0.164 H 265.5°. Best body text is #FFFFFF at 5.27:1 contrast (WCAG AA passes).

Color values

HEX	#3F66CC
RGB	rgb(63, 102, 204)
HSL	hsl(223, 58%, 52%)
HSV	hsv(223, 69%, 80%)
CMYK	cmyk(69.1%, 50%, 0%, 20%)
CIE-LAB	lab(45.52, 20.33, -57.04)
CIE-LCH	lch(45.52, 60.55, 289.62°)
OKLab	oklab(53.76% -0.013 -0.1637)
OKLCH	oklch(53.76% 0.164 265.5)
XYZ	xyz(17.6965, 14.9174, 59.0617)
Luminance	0.1492 (WCAG relative)
Temperature	cool
Family	blue

Closest named colors

Perceptual scales

Shades

Tints

Tones

OKLCH scale

Color harmonies

complementary

#3F66CC #CCA53F

analogous

#3FADCC #3F66CC #5E3FCC

triadic

#3F66CC #CC3F66 #66CC3F

tetradic

#3F66CC #CC3FAD #CCA53F #3FCC5E

square

#3F66CC #CC3FAD #CCA53F #3FCC5E

split-complementary

#3F66CC #CC5E3F #ADCC3F

monochromatic

#1E3672 #2B4CA3 #3F66CC #6F8DD9 #A0B3E6

Accessibility & contrast

On white

5.27

#3F66CC on #FFFFFF

AA ✓AA large ✓AAA ✗

On black

3.98

#3F66CC on #000000

AA ✗AA large ✓AAA ✗

Best text color

#FFFFFF on #3F66CC

5.27:1 — WCAG AA (normal text) passes

Contrast matrix

fg \ bg	##3F66CC	#FFFFFF	#000000	##FFFFFF
##3F66CC	1.00	5.27	3.98	5.27
#FFFFFF	5.27	1.00	21.00	1.00
#000000	3.98	21.00	1.00	21.00
##FFFFFF	5.27	1.00	21.00	1.00

Color blindness preview

Protanopia (red-blind)

#2B73D0

Deuteranopia (green-blind)

#0066CA

Tritanopia (blue-blind)

#007E8F

Achromatopsia (no color)

#6C6C6C

Design tokens & code

CSS

--color: #3f66cc;
/* rgb */ color: rgb(63, 102, 204);
/* oklch */ color: oklch(53.8% 0.164 265.5);

Tailwind

colors: {
  custom: {
    50: '#8491dc',
    500: '#3f66cc',
    950: '#000000',
  },
}

SCSS

$custom: #3f66cc;
$custom-light: #8491dc;
$custom-dark: #000000;

JSON

{
  "hex": "#3f66cc",
  "rgb": {
    "r": 63,
    "g": 102,
    "b": 204
  },
  "hsl": {
    "h": 223.404,
    "s": 58.025,
    "l": 52.353
  },
  "oklch": {
    "l": 0.53756,
    "c": 0.16427,
    "h": 265.5
  },
  "luminance": 0.14919
}

Semantic roles & 50–950 ramp

primary

#3F66CC

secondary

#D2C195

accent

#B647E1

background

#F8F8FD

surface

#F0F0FB

border

#CBCBD4

text

#0C0C15

muted

#7D7D83

Preview Lab

Preview with #3F66CC

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

Preview Lab → · Contrast checker → · Palette generator →