#3F37CB#3F37CB

#3F37CB is a mid, highly saturated blue. Relative luminance 0.081; OKLCH L 45.4% C 0.218 H 275.7°. Best body text is #FFFFFF at 8.01:1 contrast (WCAG AA passes).

Color values

HEX	#3F37CB
RGB	rgb(63, 55, 203)
HSL	hsl(243, 59%, 51%)
HSV	hsv(243, 73%, 80%)
CMYK	cmyk(69%, 72.9%, 0%, 20.4%)
CIE-LAB	lab(34.19, 48.93, -74.94)
CIE-LCH	lch(34.19, 89.50, 303.14°)
OKLab	oklab(45.37% 0.0216 -0.2166)
OKLCH	oklch(45.37% 0.218 275.7)
XYZ	xyz(14.1920, 8.0996, 57.3038)
Luminance	0.0810 (WCAG relative)
Temperature	cool
Family	blue

Closest named colors

Blue With A Hint Of Purple

Perceptual scales

Shades

Tints

Tones

OKLCH scale

Color harmonies

complementary

#3F37CB #C3CB37

analogous

#3779CB #3F37CB #8937CB

triadic

#3F37CB #CB3F37 #37CB3F

tetradic

#3F37CB #CB3779 #C3CB37 #37CB89

square

#3F37CB #CB3779 #C3CB37 #37CB89

split-complementary

#3F37CB #CB8937 #79CB37

monochromatic

#201C6C #2F299C #3F37CB #6E68D8 #9C98E4

Accessibility & contrast

On white

8.01

#3F37CB on #FFFFFF

AA ✓AA large ✓AAA ✓

On black

2.62

#3F37CB on #000000

AA ✗AA large ✗AAA ✗

Best text color

#FFFFFF on #3F37CB

8.01:1 — WCAG AA (normal text) passes

Contrast matrix

fg \ bg	##3F37CB	#FFFFFF	#000000	##FFFFFF
##3F37CB	1.00	8.01	2.62	8.01
#FFFFFF	8.01	1.00	21.00	1.00
#000000	2.62	21.00	1.00	21.00
##FFFFFF	8.01	1.00	21.00	1.00

Color blindness preview

Protanopia (red-blind)

#0057CF

Deuteranopia (green-blind)

#004AC8

Tritanopia (blue-blind)

#00617E

Achromatopsia (no color)

#505050

Design tokens & code

CSS

--color: #3f37cb;
/* rgb */ color: rgb(63, 55, 203);
/* oklch */ color: oklch(45.4% 0.218 275.7);

Tailwind

colors: {
  custom: {
    50: '#8770dc',
    500: '#3f37cb',
    950: '#000000',
  },
}

SCSS

$custom: #3f37cb;
$custom-light: #8770dc;
$custom-dark: #000000;

JSON

{
  "hex": "#3f37cb",
  "rgb": {
    "r": 63,
    "g": 55,
    "b": 203
  },
  "hsl": {
    "h": 243.243,
    "s": 58.73,
    "l": 50.588
  },
  "oklch": {
    "l": 0.45365,
    "c": 0.21768,
    "h": 275.7
  },
  "luminance": 0.08101
}

Semantic roles & 50–950 ramp

primary

#3F37CB

secondary

#CCD08E

accent

#E246D9

background

#F9F6FD

surface

#F1ECFB

border

#CBC7D4

text

#0D0715

muted

#7E7A83

Preview Lab

Preview with #3F37CB

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

Preview Lab → · Contrast checker → · Palette generator →