#3781CB#3781CB

#3781CB is a mid, vivid cyan. Relative luminance 0.208; OKLCH L 59.2% C 0.135 H 251.2°. Best body text is #000000 at 5.16:1 contrast (WCAG AA passes).

Color values

HEX	#3781CB
RGB	rgb(55, 129, 203)
HSL	hsl(210, 59%, 51%)
HSV	hsv(210, 73%, 80%)
CMYK	cmyk(72.9%, 36.5%, 0%, 20.4%)
CIE-LAB	lab(52.75, 2.03, -44.92)
CIE-LCH	lch(52.75, 44.96, 272.59°)
OKLab	oklab(59.24% -0.0435 -0.1278)
OKLCH	oklch(59.24% 0.135 251.2)
XYZ	xyz(20.2013, 20.8223, 59.4428)
Luminance	0.2082 (WCAG relative)
Temperature	cool
Family	cyan

Closest named colors

Perceptual scales

Shades

Tints

Tones

OKLCH scale

Color harmonies

complementary

#3781CB #CB8137

analogous

#37CBCB #3781CB #3737CB

triadic

#3781CB #CB3781 #81CB37

tetradic

#3781CB #CB37CB #CB8137 #37CB37

square

#3781CB #CB37CB #CB8137 #37CB37

split-complementary

#3781CB #CB3737 #CBCB37

monochromatic

#1C446C #29629C #3781CB #68A0D8 #98BEE4

Accessibility & contrast

On white

4.07

#3781CB on #FFFFFF

AA ✗AA large ✓AAA ✗

On black

5.16

#3781CB on #000000

AA ✓AA large ✓AAA ✗

Best text color

#000000 on #3781CB

5.16:1 — WCAG AA (normal text) passes

Contrast matrix

fg \ bg	##3781CB	#FFFFFF	#000000	##000000
##3781CB	1.00	4.07	5.16	5.16
#FFFFFF	4.07	1.00	21.00	21.00
#000000	5.16	21.00	1.00	1.00
##000000	5.16	21.00	1.00	1.00

Color blindness preview

Protanopia (red-blind)

#5F85CE

Deuteranopia (green-blind)

#4978CA

Tritanopia (blue-blind)

#00929C

Achromatopsia (no color)

#7E7E7E

Design tokens & code

CSS

--color: #3781cb;
/* rgb */ color: rgb(55, 129, 203);
/* oklch */ color: oklch(59.2% 0.135 251.2);

Tailwind

colors: {
  custom: {
    50: '#80a5db',
    500: '#3781cb',
    950: '#000000',
  },
}

SCSS

$custom: #3781cb;
$custom-light: #80a5db;
$custom-dark: #000000;

JSON

{
  "hex": "#3781cb",
  "rgb": {
    "r": 55,
    "g": 129,
    "b": 203
  },
  "hsl": {
    "h": 210,
    "s": 58.73,
    "l": 50.588
  },
  "oklch": {
    "l": 0.59244,
    "c": 0.13503,
    "h": 251.2
  },
  "luminance": 0.20825
}

Semantic roles & 50–950 ramp

primary

#3781CB

secondary

#D0AF8E

accent

#9446E2

background

#F8FAFD

surface

#F0F4FB

border

#CBCED4

text

#0C0F15

muted

#7D7F83

Preview Lab

Preview with #3781CB

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

Preview Lab → · Contrast checker → · Palette generator →