#3F57BB#3F57BB

#3F57BB is a mid, vivid blue. Relative luminance 0.115; OKLCH L 49.5% C 0.160 H 269.6°. Best body text is #FFFFFF at 6.38:1 contrast (WCAG AA passes).

Color values

HEX	#3F57BB
RGB	rgb(63, 87, 187)
HSL	hsl(228, 50%, 49%)
HSV	hsv(228, 66%, 73%)
CMYK	cmyk(66.3%, 53.5%, 0%, 26.7%)
CIE-LAB	lab(40.34, 23.84, -55.55)
CIE-LCH	lch(40.34, 60.45, 293.23°)
OKLab	oklab(49.47% -0.0012 -0.1596)
OKLCH	oklch(49.47% 0.16 269.6)
XYZ	xyz(14.4247, 11.4597, 48.4558)
Luminance	0.1146 (WCAG relative)
Temperature	cool
Family	blue

Closest named colors

Perceptual scales

Shades

Tints

Tones

OKLCH scale

Color harmonies

complementary

#3F57BB #BBA33F

analogous

#3F95BB #3F57BB #653FBB

triadic

#3F57BB #BB3F57 #57BB3F

tetradic

#3F57BB #BB3F95 #BBA33F #3FBB65

square

#3F57BB #BB3F95 #BBA33F #3FBB65

split-complementary

#3F57BB #BB653F #95BB3F

monochromatic

#202C5F #30428D #3F57BB #6A7DCD #98A5DC

Accessibility & contrast

On white

6.38

#3F57BB on #FFFFFF

AA ✓AA large ✓AAA ✗

On black

3.29

#3F57BB on #000000

AA ✗AA large ✓AAA ✗

Best text color

#FFFFFF on #3F57BB

6.38:1 — WCAG AA (normal text) passes

Contrast matrix

fg \ bg	##3F57BB	#FFFFFF	#000000	##FFFFFF
##3F57BB	1.00	6.38	3.29	6.38
#FFFFFF	6.38	1.00	21.00	1.00
#000000	3.29	21.00	1.00	21.00
##FFFFFF	6.38	1.00	21.00	1.00

Color blindness preview

Protanopia (red-blind)

#1265BF

Deuteranopia (green-blind)

#005AB9

Tritanopia (blue-blind)

#006F80

Achromatopsia (no color)

#5F5F5F

Design tokens & code

CSS

--color: #3f57bb;
/* rgb */ color: rgb(63, 87, 187);
/* oklch */ color: oklch(49.5% 0.160 269.6);

Tailwind

colors: {
  custom: {
    50: '#8286d0',
    500: '#3f57bb',
    950: '#000000',
  },
}

SCSS

$custom: #3f57bb;
$custom-light: #8286d0;
$custom-dark: #000000;

JSON

{
  "hex": "#3f57bb",
  "rgb": {
    "r": 63,
    "g": 87,
    "b": 187
  },
  "hsl": {
    "h": 228.387,
    "s": 49.6,
    "l": 49.02
  },
  "oklch": {
    "l": 0.49467,
    "c": 0.15959,
    "h": 269.6
  },
  "luminance": 0.11461
}

Semantic roles & 50–950 ramp

primary

#3F57BB

secondary

#C8BD8E

accent

#BE4FD9

background

#F8F8FC

surface

#F0EFF9

border

#CBCAD2

text

#0C0B14

muted

#7D7C82

Preview Lab

Preview with #3F57BB

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

Preview Lab → · Contrast checker → · Palette generator →