#3731B8#3731B8

#3731B8 is a dark, highly saturated blue. Relative luminance 0.065; OKLCH L 42.1% C 0.203 H 275.2°. Best body text is #FFFFFF at 9.15:1 contrast (WCAG AA passes).

Color values

HEX	#3731B8
RGB	rgb(55, 49, 184)
HSL	hsl(243, 58%, 46%)
HSV	hsv(243, 73%, 72%)
CMYK	cmyk(70.1%, 73.4%, 0%, 27.8%)
CIE-LAB	lab(30.57, 45.31, -69.78)
CIE-LCH	lch(30.57, 83.20, 303.00°)
OKLab	oklab(42.08% 0.0184 -0.2017)
OKLCH	oklch(42.08% 0.203 275.2)
XYZ	xyz(11.3227, 6.4685, 45.9899)
Luminance	0.0647 (WCAG relative)
Temperature	cool
Family	blue

Closest named colors

Sapphire (survey)

#2138AB

ΔE00 3.95

Blue With A Hint Of Purple

Perceptual scales

Shades

Tints

Tones

OKLCH scale

Color harmonies

complementary

#3731B8 #B2B831

analogous

#316EB8 #3731B8 #7B31B8

triadic

#3731B8 #B83731 #31B837

tetradic

#3731B8 #B8316E #B2B831 #31B87B

square

#3731B8 #B8316E #B2B831 #31B87B

split-complementary

#3731B8 #B87B31 #6EB831

monochromatic

#1A1757 #292488 #3731B8 #5A55D2 #8985DE

Accessibility & contrast

On white

9.15

#3731B8 on #FFFFFF

AA ✓AA large ✓AAA ✓

On black

2.29

#3731B8 on #000000

AA ✗AA large ✗AAA ✗

Best text color

#FFFFFF on #3731B8

9.15:1 — WCAG AA (normal text) passes

Contrast matrix

fg \ bg	##3731B8	#FFFFFF	#000000	##FFFFFF
##3731B8	1.00	9.15	2.29	9.15
#FFFFFF	9.15	1.00	21.00	1.00
#000000	2.29	21.00	1.00	21.00
##FFFFFF	9.15	1.00	21.00	1.00

Color blindness preview

Protanopia (red-blind)

#004EBC

Deuteranopia (green-blind)

#0042B6

Tritanopia (blue-blind)

#005772

Achromatopsia (no color)

#484848

Design tokens & code

CSS

--color: #3731b8;
/* rgb */ color: rgb(55, 49, 184);
/* oklch */ color: oklch(42.1% 0.203 275.2);

Tailwind

colors: {
  custom: {
    50: '#816bcf',
    500: '#3731b8',
    950: '#000000',
  },
}

SCSS

$custom: #3731b8;
$custom-light: #816bcf;
$custom-dark: #000000;

JSON

{
  "hex": "#3731b8",
  "rgb": {
    "r": 55,
    "g": 49,
    "b": 184
  },
  "hsl": {
    "h": 242.667,
    "s": 57.94,
    "l": 45.686
  },
  "oklch": {
    "l": 0.42081,
    "c": 0.20256,
    "h": 275.2
  },
  "luminance": 0.0647
}

Semantic roles & 50–950 ramp

primary

#3731B8

secondary

#C5C87D

accent

#E147DA

background

#F8F6FC

surface

#F0EBF9

border

#CBC6D2

text

#0C0714

muted

#7D7A82

Preview Lab

Preview with #3731B8

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

Preview Lab → · Contrast checker → · Palette generator →