#3F66BC#3F66BC

#3F66BC is a mid, vivid blue. Relative luminance 0.142; OKLCH L 52.7% C 0.142 H 263.8°. Best body text is #FFFFFF at 5.47:1 contrast (WCAG AA passes).

Color values

HEX	#3F66BC
RGB	rgb(63, 102, 188)
HSL	hsl(221, 50%, 49%)
HSV	hsv(221, 66%, 74%)
CMYK	cmyk(66.5%, 45.7%, 0%, 26.3%)
CIE-LAB	lab(44.50, 14.57, -49.44)
CIE-LCH	lch(44.50, 51.54, 286.42°)
OKLab	oklab(52.65% -0.0152 -0.1414)
OKLCH	oklch(52.65% 0.142 263.8)
XYZ	xyz(15.8752, 14.1888, 49.4693)
Luminance	0.1419 (WCAG relative)
Temperature	cool
Family	blue

Closest named colors

Perceptual scales

Shades

Tints

Tones

OKLCH scale

Color harmonies

complementary

#3F66BC #BC953F

analogous

#3FA5BC #3F66BC #573FBC

triadic

#3F66BC #BC3F66 #66BC3F

tetradic

#3F66BC #BC3FA5 #BC953F #3FBC57

square

#3F66BC #BC3FA5 #BC953F #3FBC57

split-complementary

#3F66BC #BC573F #A5BC3F

monochromatic

#203460 #304D8E #3F66BC #6B8ACD #99AEDD

Accessibility & contrast

On white

5.47

#3F66BC on #FFFFFF

AA ✓AA large ✓AAA ✗

On black

3.84

#3F66BC on #000000

AA ✗AA large ✓AAA ✗

Best text color

#FFFFFF on #3F66BC

5.47:1 — WCAG AA (normal text) passes

Contrast matrix

fg \ bg	##3F66BC	#FFFFFF	#000000	##FFFFFF
##3F66BC	1.00	5.47	3.84	5.47
#FFFFFF	5.47	1.00	21.00	1.00
#000000	3.84	21.00	1.00	21.00
##FFFFFF	5.47	1.00	21.00	1.00

Color blindness preview

Protanopia (red-blind)

#3B6FBF

Deuteranopia (green-blind)

#2464BA

Tritanopia (blue-blind)

#007A88

Achromatopsia (no color)

#696969

Design tokens & code

CSS

--color: #3f66bc;
/* rgb */ color: rgb(63, 102, 188);
/* oklch */ color: oklch(52.7% 0.142 263.8);

Tailwind

colors: {
  custom: {
    50: '#8191d1',
    500: '#3f66bc',
    950: '#000000',
  },
}

SCSS

$custom: #3f66bc;
$custom-light: #8191d1;
$custom-dark: #000000;

JSON

{
  "hex": "#3f66bc",
  "rgb": {
    "r": 63,
    "g": 102,
    "b": 188
  },
  "hsl": {
    "h": 221.28,
    "s": 49.801,
    "l": 49.216
  },
  "oklch": {
    "l": 0.52651,
    "c": 0.1422,
    "h": 263.8
  },
  "luminance": 0.1419
}

Semantic roles & 50–950 ramp

primary

#3F66BC

secondary

#C9B68E

accent

#AE4ED9

background

#F8F8FC

surface

#F0F0F9

border

#CBCBD2

text

#0B0C14

muted

#7C7D82

Preview Lab

Preview with #3F66BC

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

Preview Lab → · Contrast checker → · Palette generator →