#3731B7#3731B7

#3731B7 is a dark, highly saturated blue. Relative luminance 0.064; OKLCH L 42.0% C 0.201 H 275.3°. Best body text is #FFFFFF at 9.19:1 contrast (WCAG AA passes).

Color values

HEX	#3731B7
RGB	rgb(55, 49, 183)
HSL	hsl(243, 58%, 45%)
HSV	hsv(243, 73%, 72%)
CMYK	cmyk(69.9%, 73.2%, 0%, 28.2%)
CIE-LAB	lab(30.46, 44.99, -69.35)
CIE-LCH	lch(30.46, 82.66, 302.97°)
OKLab	oklab(41.98% 0.0186 -0.2005)
OKLCH	oklch(41.98% 0.201 275.3)
XYZ	xyz(11.2183, 6.4267, 45.4398)
Luminance	0.0643 (WCAG relative)
Temperature	cool
Family	blue

Closest named colors

Sapphire (survey)

#2138AB

ΔE00 3.88

Blue With A Hint Of Purple

Perceptual scales

Shades

Tints

Tones

OKLCH scale

Color harmonies

complementary

#3731B7 #B1B731

analogous

#316EB7 #3731B7 #7A31B7

triadic

#3731B7 #B73731 #31B737

tetradic

#3731B7 #B7316E #B1B731 #31B77A

square

#3731B7 #B7316E #B1B731 #31B77A

split-complementary

#3731B7 #B77A31 #6EB731

monochromatic

#1A1756 #282487 #3731B7 #5A54D1 #8884DE

Accessibility & contrast

On white

9.19

#3731B7 on #FFFFFF

AA ✓AA large ✓AAA ✓

On black

2.29

#3731B7 on #000000

AA ✗AA large ✗AAA ✗

Best text color

#FFFFFF on #3731B7

9.19:1 — WCAG AA (normal text) passes

Contrast matrix

fg \ bg	##3731B7	#FFFFFF	#000000	##FFFFFF
##3731B7	1.00	9.19	2.29	9.19
#FFFFFF	9.19	1.00	21.00	1.00
#000000	2.29	21.00	1.00	21.00
##FFFFFF	9.19	1.00	21.00	1.00

Color blindness preview

Protanopia (red-blind)

#004EBB

Deuteranopia (green-blind)

#0042B5

Tritanopia (blue-blind)

#005771

Achromatopsia (no color)

#484848

Design tokens & code

CSS

--color: #3731b7;
/* rgb */ color: rgb(55, 49, 183);
/* oklch */ color: oklch(42.0% 0.201 275.3);

Tailwind

colors: {
  custom: {
    50: '#806bce',
    500: '#3731b7',
    950: '#000000',
  },
}

SCSS

$custom: #3731b7;
$custom-light: #806bce;
$custom-dark: #000000;

JSON

{
  "hex": "#3731b7",
  "rgb": {
    "r": 55,
    "g": 49,
    "b": 183
  },
  "hsl": {
    "h": 242.687,
    "s": 57.759,
    "l": 45.49
  },
  "oklch": {
    "l": 0.4198,
    "c": 0.20133,
    "h": 275.3
  },
  "luminance": 0.06428
}

Semantic roles & 50–950 ramp

primary

#3731B7

secondary

#C4C87C

accent

#E147DA

background

#F8F6FC

surface

#F0EBF9

border

#CBC6D2

text

#0C0714

muted

#7D7A82

Preview Lab

Preview with #3731B7

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

Preview Lab → · Contrast checker → · Palette generator →