#1B3F8B#1B3F8B

#1B3F8B is a dark, vivid blue. Relative luminance 0.057; OKLCH L 39.0% C 0.134 H 262.8°. Best body text is #FFFFFF at 9.86:1 contrast (WCAG AA passes).

Color values

HEX	#1B3F8B
RGB	rgb(27, 63, 139)
HSL	hsl(221, 67%, 33%)
HSV	hsv(221, 81%, 55%)
CMYK	cmyk(80.6%, 54.7%, 0%, 45.5%)
CIE-LAB	lab(28.52, 16.58, -45.96)
CIE-LCH	lch(28.52, 48.86, 289.84°)
OKLab	oklab(38.95% -0.0168 -0.1325)
OKLCH	oklch(38.95% 0.134 262.8)
XYZ	xyz(6.8880, 5.6513, 25.1489)
Luminance	0.0565 (WCAG relative)
Temperature	cool
Family	blue

Closest named colors

Perceptual scales

Shades

Tints

Tones

OKLCH scale

Color harmonies

complementary

#1B3F8B #8B671B

analogous

#1B778B #1B3F8B #2F1B8B

triadic

#1B3F8B #8B1B3F #3F8B1B

tetradic

#1B3F8B #8B1B77 #8B671B #1B8B2F

square

#1B3F8B #8B1B77 #8B671B #1B8B2F

split-complementary

#1B3F8B #8B2F1B #778B1B

monochromatic

#071125 #112858 #1B3F8B #2556BE #4576DB

Accessibility & contrast

On white

9.86

#1B3F8B on #FFFFFF

AA ✓AA large ✓AAA ✓

On black

2.13

#1B3F8B on #000000

AA ✗AA large ✗AAA ✗

Best text color

#FFFFFF on #1B3F8B

9.86:1 — WCAG AA (normal text) passes

Contrast matrix

fg \ bg	##1B3F8B	#FFFFFF	#000000	##FFFFFF
##1B3F8B	1.00	9.86	2.13	9.86
#FFFFFF	9.86	1.00	21.00	1.00
#000000	2.13	21.00	1.00	21.00
##FFFFFF	9.86	1.00	21.00	1.00

Color blindness preview

Protanopia (red-blind)

#04498E

Deuteranopia (green-blind)

#003E8A

Tritanopia (blue-blind)

#00525E

Achromatopsia (no color)

#434343

Design tokens & code

CSS

--color: #1b3f8b;
/* rgb */ color: rgb(27, 63, 139);
/* oklch */ color: oklch(39.0% 0.134 262.8);

Tailwind

colors: {
  custom: {
    50: '#6a73ad',
    500: '#1b3f8b',
    950: '#000000',
  },
}

SCSS

$custom: #1b3f8b;
$custom-light: #6a73ad;
$custom-dark: #000000;

JSON

{
  "hex": "#1b3f8b",
  "rgb": {
    "r": 27,
    "g": 63,
    "b": 139
  },
  "hsl": {
    "h": 220.714,
    "s": 67.47,
    "l": 32.549
  },
  "oklch": {
    "l": 0.38952,
    "c": 0.13355,
    "h": 262.8
  },
  "luminance": 0.05652
}

Semantic roles & 50–950 ramp

primary

#1B3F8B

secondary

#BC9645

accent

#B33DEA

background

#F6F6FA

surface

#ECECF4

border

#C7C7CE

text

#080810

muted

#7A7B7F

Preview Lab

Preview with #1B3F8B

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

Preview Lab → · Contrast checker → · Palette generator →