#3F42BB#3F42BB

#3F42BB is a mid, vivid blue. Relative luminance 0.085; OKLCH L 45.6% C 0.186 H 275.1°. Best body text is #FFFFFF at 7.75:1 contrast (WCAG AA passes).

Color values

HEX	#3F42BB
RGB	rgb(63, 66, 187)
HSL	hsl(239, 50%, 49%)
HSV	hsv(239, 66%, 73%)
CMYK	cmyk(66.3%, 64.7%, 0%, 26.7%)
CIE-LAB	lab(35.08, 37.20, -64.11)
CIE-LCH	lch(35.08, 74.12, 300.12°)
OKLab	oklab(45.56% 0.0165 -0.1849)
OKLCH	oklch(45.56% 0.186 275.1)
XYZ	xyz(12.9648, 8.5399, 47.9692)
Luminance	0.0854 (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

#3F42BB #BBB83F

analogous

#3F80BB #3F42BB #7A3FBB

triadic

#3F42BB #BB3F42 #42BB3F

tetradic

#3F42BB #BB3F80 #BBB83F #3FBB7A

square

#3F42BB #BB3F80 #BBB83F #3FBB7A

split-complementary

#3F42BB #BB7A3F #80BB3F

monochromatic

#20225F #30328D #3F42BB #6A6DCD #989ADC

Accessibility & contrast

On white

7.75

#3F42BB on #FFFFFF

AA ✓AA large ✓AAA ✓

On black

2.71

#3F42BB on #000000

AA ✗AA large ✗AAA ✗

Best text color

#FFFFFF on #3F42BB

7.75:1 — WCAG AA (normal text) passes

Contrast matrix

fg \ bg	##3F42BB	#FFFFFF	#000000	##FFFFFF
##3F42BB	1.00	7.75	2.71	7.75
#FFFFFF	7.75	1.00	21.00	1.00
#000000	2.71	21.00	1.00	21.00
##FFFFFF	7.75	1.00	21.00	1.00

Color blindness preview

Protanopia (red-blind)

#0058BF

Deuteranopia (green-blind)

#004DB9

Tritanopia (blue-blind)

#006178

Achromatopsia (no color)

#525252

Design tokens & code

CSS

--color: #3f42bb;
/* rgb */ color: rgb(63, 66, 187);
/* oklch */ color: oklch(45.6% 0.186 275.1);

Tailwind

colors: {
  custom: {
    50: '#8377d0',
    500: '#3f42bb',
    950: '#000000',
  },
}

SCSS

$custom: #3f42bb;
$custom-light: #8377d0;
$custom-dark: #000000;

JSON

{
  "hex": "#3f42bb",
  "rgb": {
    "r": 63,
    "g": 66,
    "b": 187
  },
  "hsl": {
    "h": 238.548,
    "s": 49.6,
    "l": 49.02
  },
  "oklch": {
    "l": 0.45561,
    "c": 0.18567,
    "h": 275.1
  },
  "luminance": 0.08541
}

Semantic roles & 50–950 ramp

primary

#3F42BB

secondary

#C8C78E

accent

#D64FD9

background

#F8F7FC

surface

#F0EDF9

border

#CBC8D2

text

#0C0814

muted

#7D7B82

Preview Lab

Preview with #3F42BB

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

Preview Lab → · Contrast checker → · Palette generator →