#3731B9#3731B9

#3731B9 is a dark, highly saturated blue. Relative luminance 0.065; OKLCH L 42.2% C 0.204 H 275.1°. Best body text is #FFFFFF at 9.12:1 contrast (WCAG AA passes).

Color values

HEX	#3731B9
RGB	rgb(55, 49, 185)
HSL	hsl(243, 58%, 46%)
HSV	hsv(243, 74%, 73%)
CMYK	cmyk(70.3%, 73.5%, 0%, 27.5%)
CIE-LAB	lab(30.67, 45.64, -70.20)
CIE-LCH	lch(30.67, 83.73, 303.03°)
OKLab	oklab(42.18% 0.0182 -0.203)
OKLCH	oklch(42.18% 0.204 275.1)
XYZ	xyz(11.4279, 6.5106, 46.5439)
Luminance	0.0651 (WCAG relative)
Temperature	cool
Family	blue

Closest named colors

Sapphire (survey)

#2138AB

ΔE00 4.02

Blue With A Hint Of Purple

Perceptual scales

Shades

Tints

Tones

OKLCH scale

Color harmonies

complementary

#3731B9 #B3B931

analogous

#316FB9 #3731B9 #7B31B9

triadic

#3731B9 #B93731 #31B937

tetradic

#3731B9 #B9316F #B3B931 #31B97B

square

#3731B9 #B9316F #B3B931 #31B97B

split-complementary

#3731B9 #B97B31 #6FB931

monochromatic

#1A1758 #292489 #3731B9 #5B55D2 #8A86DF

Accessibility & contrast

On white

9.12

#3731B9 on #FFFFFF

AA ✓AA large ✓AAA ✓

On black

2.30

#3731B9 on #000000

AA ✗AA large ✗AAA ✗

Best text color

#FFFFFF on #3731B9

9.12:1 — WCAG AA (normal text) passes

Contrast matrix

fg \ bg	##3731B9	#FFFFFF	#000000	##FFFFFF
##3731B9	1.00	9.12	2.30	9.12
#FFFFFF	9.12	1.00	21.00	1.00
#000000	2.30	21.00	1.00	21.00
##FFFFFF	9.12	1.00	21.00	1.00

Color blindness preview

Protanopia (red-blind)

#004EBD

Deuteranopia (green-blind)

#0042B7

Tritanopia (blue-blind)

#005872

Achromatopsia (no color)

#484848

Design tokens & code

CSS

--color: #3731b9;
/* rgb */ color: rgb(55, 49, 185);
/* oklch */ color: oklch(42.2% 0.204 275.1);

Tailwind

colors: {
  custom: {
    50: '#816bcf',
    500: '#3731b9',
    950: '#000000',
  },
}

SCSS

$custom: #3731b9;
$custom-light: #816bcf;
$custom-dark: #000000;

JSON

{
  "hex": "#3731b9",
  "rgb": {
    "r": 55,
    "g": 49,
    "b": 185
  },
  "hsl": {
    "h": 242.647,
    "s": 58.12,
    "l": 45.882
  },
  "oklch": {
    "l": 0.42183,
    "c": 0.20378,
    "h": 275.1
  },
  "luminance": 0.06512
}

Semantic roles & 50–950 ramp

primary

#3731B9

secondary

#C5C87D

accent

#E146DB

background

#F8F6FC

surface

#F0EBF9

border

#CBC6D2

text

#0C0714

muted

#7D7A82

Preview Lab

Preview with #3731B9

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

Preview Lab → · Contrast checker → · Palette generator →