#637BDF#637BDF

#637BDF is a mid, vivid blue. Relative luminance 0.221; OKLCH L 61.2% C 0.153 H 271.1°. Best body text is #000000 at 5.43:1 contrast (WCAG AA passes).

Color values

HEX	#637BDF
RGB	rgb(99, 123, 223)
HSL	hsl(228, 66%, 63%)
HSV	hsv(228, 56%, 87%)
CMYK	cmyk(55.6%, 44.8%, 0%, 12.5%)
CIE-LAB	lab(54.18, 20.16, -53.83)
CIE-LCH	lch(54.18, 57.48, 290.54°)
OKLab	oklab(61.24% 0.003 -0.1533)
OKLCH	oklch(61.24% 0.153 271.1)
XYZ	xyz(25.5434, 22.1444, 72.7260)
Luminance	0.2215 (WCAG relative)
Temperature	cool
Family	blue

Closest named colors

Perceptual scales

Shades

Tints

Tones

OKLCH scale

Color harmonies

complementary

#637BDF #DFC763

analogous

#63B9DF #637BDF #8963DF

triadic

#637BDF #DF637B #7BDF63

tetradic

#637BDF #DF63B9 #DFC763 #63DF89

square

#637BDF #DF63B9 #DFC763 #63DF89

split-complementary

#637BDF #DF8963 #B9DF63

monochromatic

#223BA6 #3050D5 #637BDF #96A6E9 #C9D1F4

Accessibility & contrast

On white

3.87

#637BDF on #FFFFFF

AA ✗AA large ✓AAA ✗

On black

5.43

#637BDF on #000000

AA ✓AA large ✓AAA ✗

Best text color

#000000 on #637BDF

5.43:1 — WCAG AA (normal text) passes

Contrast matrix

fg \ bg	##637BDF	#FFFFFF	#000000	##000000
##637BDF	1.00	3.87	5.43	5.43
#FFFFFF	3.87	1.00	21.00	21.00
#000000	5.43	21.00	1.00	1.00
##000000	5.43	21.00	1.00	1.00

Color blindness preview

Protanopia (red-blind)

#4E87E3

Deuteranopia (green-blind)

#3E7CDD

Tritanopia (blue-blind)

#1991A2

Achromatopsia (no color)

#828282

Design tokens & code

CSS

--color: #637bdf;
/* rgb */ color: rgb(99, 123, 223);
/* oklch */ color: oklch(61.2% 0.153 271.1);

Tailwind

colors: {
  custom: {
    50: '#98a0e9',
    500: '#637bdf',
    950: '#000000',
  },
}

SCSS

$custom: #637bdf;
$custom-light: #98a0e9;
$custom-dark: #000000;

JSON

{
  "hex": "#637bdf",
  "rgb": {
    "r": 99,
    "g": 123,
    "b": 223
  },
  "hsl": {
    "h": 228.387,
    "s": 65.957,
    "l": 63.137
  },
  "oklch": {
    "l": 0.61242,
    "c": 0.15332,
    "h": 271.1
  },
  "luminance": 0.22146
}

Semantic roles & 50–950 ramp

primary

#637BDF

secondary

#E5DDB9

accent

#AB18CE

background

#F9F9FE

surface

#F2F2FD

border

#CCCCD5

text

#0E0E16

muted

#7E7E84

Preview Lab

Preview with #637BDF

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

Preview Lab → · Contrast checker → · Palette generator →