#3666B3#3666B3

#3666B3 is a mid, vivid blue. Relative luminance 0.135; OKLCH L 51.6% C 0.133 H 259.5°. Best body text is #FFFFFF at 5.66:1 contrast (WCAG AA passes).

Color values

HEX	#3666B3
RGB	rgb(54, 102, 179)
HSL	hsl(217, 54%, 46%)
HSV	hsv(217, 70%, 70%)
CMYK	cmyk(69.8%, 43%, 0%, 29.8%)
CIE-LAB	lab(43.57, 9.84, -45.71)
CIE-LCH	lch(43.57, 46.76, 282.15°)
OKLab	oklab(51.65% -0.0243 -0.1306)
OKLCH	oklch(51.65% 0.133 259.5)
XYZ	xyz(14.4064, 13.5402, 44.4934)
Luminance	0.1354 (WCAG relative)
Temperature	cool
Family	blue

Closest named colors

Perceptual scales

Shades

Tints

Tones

OKLCH scale

Color harmonies

complementary

#3666B3 #B38336

analogous

#36A4B3 #3666B3 #4436B3

triadic

#3666B3 #B33666 #66B336

tetradic

#3666B3 #B336A4 #B38336 #36B344

square

#3666B3 #B336A4 #B38336 #36B344

split-complementary

#3666B3 #B34436 #A4B336

monochromatic

#1A3055 #284B84 #3666B3 #5986CD #88A8DB

Accessibility & contrast

On white

5.66

#3666B3 on #FFFFFF

AA ✓AA large ✓AAA ✗

On black

3.71

#3666B3 on #000000

AA ✗AA large ✓AAA ✗

Best text color

#FFFFFF on #3666B3

5.66:1 — WCAG AA (normal text) passes

Contrast matrix

fg \ bg	##3666B3	#FFFFFF	#000000	##FFFFFF
##3666B3	1.00	5.66	3.71	5.66
#FFFFFF	5.66	1.00	21.00	1.00
#000000	3.71	21.00	1.00	21.00
##FFFFFF	5.66	1.00	21.00	1.00

Color blindness preview

Protanopia (red-blind)

#416DB6

Deuteranopia (green-blind)

#2C62B1

Tritanopia (blue-blind)

#007884

Achromatopsia (no color)

#676767

Design tokens & code

CSS

--color: #3666b3;
/* rgb */ color: rgb(54, 102, 179);
/* oklch */ color: oklch(51.6% 0.133 259.5);

Tailwind

colors: {
  custom: {
    50: '#7c91ca',
    500: '#3666b3',
    950: '#000000',
  },
}

SCSS

$custom: #3666b3;
$custom-light: #7c91ca;
$custom-dark: #000000;

JSON

{
  "hex": "#3666b3",
  "rgb": {
    "r": 54,
    "g": 102,
    "b": 179
  },
  "hsl": {
    "h": 216.96,
    "s": 53.648,
    "l": 45.686
  },
  "oklch": {
    "l": 0.51647,
    "c": 0.13284,
    "h": 259.5
  },
  "luminance": 0.13542
}

Semantic roles & 50–950 ramp

primary

#3666B3

secondary

#C5AA80

accent

#A54BDD

background

#F8F8FC

surface

#EFF0F8

border

#CACBD1

text

#0B0C13

muted

#7C7D82

Preview Lab

Preview with #3666B3

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

Preview Lab → · Contrast checker → · Palette generator →