#3F66BB#3F66BB

#3F66BB is a mid, vivid blue. Relative luminance 0.141; OKLCH L 52.6% C 0.141 H 263.7°. Best body text is #FFFFFF at 5.48:1 contrast (WCAG AA passes).

Color values

HEX	#3F66BB
RGB	rgb(63, 102, 187)
HSL	hsl(221, 50%, 49%)
HSV	hsv(221, 66%, 73%)
CMYK	cmyk(66.3%, 45.5%, 0%, 26.7%)
CIE-LAB	lab(44.44, 14.21, -48.95)
CIE-LCH	lch(44.44, 50.98, 286.19°)
OKLab	oklab(52.59% -0.0154 -0.14)
OKLCH	oklch(52.59% 0.141 263.7)
XYZ	xyz(15.7678, 14.1458, 48.9035)
Luminance	0.1415 (WCAG relative)
Temperature	cool
Family	blue

Closest named colors

Perceptual scales

Shades

Tints

Tones

OKLCH scale

Color harmonies

complementary

#3F66BB #BB943F

analogous

#3FA4BB #3F66BB #563FBB

triadic

#3F66BB #BB3F66 #66BB3F

tetradic

#3F66BB #BB3FA4 #BB943F #3FBB56

square

#3F66BB #BB3FA4 #BB943F #3FBB56

split-complementary

#3F66BB #BB563F #A4BB3F

monochromatic

#20345F #304D8D #3F66BB #6A89CD #98AEDC

Accessibility & contrast

On white

5.48

#3F66BB on #FFFFFF

AA ✓AA large ✓AAA ✗

On black

3.83

#3F66BB on #000000

AA ✗AA large ✓AAA ✗

Best text color

#FFFFFF on #3F66BB

5.48:1 — WCAG AA (normal text) passes

Contrast matrix

fg \ bg	##3F66BB	#FFFFFF	#000000	##FFFFFF
##3F66BB	1.00	5.48	3.83	5.48
#FFFFFF	5.48	1.00	21.00	1.00
#000000	3.83	21.00	1.00	21.00
##FFFFFF	5.48	1.00	21.00	1.00

Color blindness preview

Protanopia (red-blind)

#3C6FBE

Deuteranopia (green-blind)

#2664B9

Tritanopia (blue-blind)

#007A87

Achromatopsia (no color)

#696969

Design tokens & code

CSS

--color: #3f66bb;
/* rgb */ color: rgb(63, 102, 187);
/* oklch */ color: oklch(52.6% 0.141 263.7);

Tailwind

colors: {
  custom: {
    50: '#8191d0',
    500: '#3f66bb',
    950: '#000000',
  },
}

SCSS

$custom: #3f66bb;
$custom-light: #8191d0;
$custom-dark: #000000;

JSON

{
  "hex": "#3f66bb",
  "rgb": {
    "r": 63,
    "g": 102,
    "b": 187
  },
  "hsl": {
    "h": 221.129,
    "s": 49.6,
    "l": 49.02
  },
  "oklch": {
    "l": 0.52585,
    "c": 0.1408,
    "h": 263.7
  },
  "luminance": 0.14147
}

Semantic roles & 50–950 ramp

primary

#3F66BB

secondary

#C8B68E

accent

#AE4FD9

background

#F8F8FC

surface

#F0F0F9

border

#CBCBD2

text

#0B0C14

muted

#7C7D82

Preview Lab

Preview with #3F66BB

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

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