#1B3A8B#1B3A8B

#1B3A8B is a dark, vivid blue. Relative luminance 0.051; OKLCH L 37.9% C 0.140 H 264.6°. Best body text is #FFFFFF at 10.37:1 contrast (WCAG AA passes).

Color values

HEX	#1B3A8B
RGB	rgb(27, 58, 139)
HSL	hsl(223, 67%, 33%)
HSV	hsv(223, 81%, 55%)
CMYK	cmyk(80.6%, 58.3%, 0%, 45.5%)
CIE-LAB	lab(27.08, 20.06, -48.29)
CIE-LCH	lch(27.08, 52.29, 292.56°)
OKLab	oklab(37.87% -0.0131 -0.1394)
OKLCH	oklch(37.87% 0.14 264.6)
XYZ	xyz(6.6236, 5.1224, 25.0607)
Luminance	0.0512 (WCAG relative)
Temperature	cool
Family	blue

Closest named colors

Perceptual scales

Shades

Tints

Tones

OKLCH scale

Color harmonies

complementary

#1B3A8B #8B6C1B

analogous

#1B728B #1B3A8B #341B8B

triadic

#1B3A8B #8B1B3A #3A8B1B

tetradic

#1B3A8B #8B1B72 #8B6C1B #1B8B34

square

#1B3A8B #8B1B72 #8B6C1B #1B8B34

split-complementary

#1B3A8B #8B341B #728B1B

monochromatic

#070F25 #112558 #1B3A8B #254FBE #456FDB

Accessibility & contrast

On white

10.37

#1B3A8B on #FFFFFF

AA ✓AA large ✓AAA ✓

On black

2.02

#1B3A8B on #000000

AA ✗AA large ✗AAA ✗

Best text color

#FFFFFF on #1B3A8B

10.37:1 — WCAG AA (normal text) passes

Contrast matrix

fg \ bg	##1B3A8B	#FFFFFF	#000000	##FFFFFF
##1B3A8B	1.00	10.37	2.02	10.37
#FFFFFF	10.37	1.00	21.00	1.00
#000000	2.02	21.00	1.00	21.00
##FFFFFF	10.37	1.00	21.00	1.00

Color blindness preview

Protanopia (red-blind)

#00458E

Deuteranopia (green-blind)

#003B89

Tritanopia (blue-blind)

#004E5C

Achromatopsia (no color)

#404040

Design tokens & code

CSS

--color: #1b3a8b;
/* rgb */ color: rgb(27, 58, 139);
/* oklch */ color: oklch(37.9% 0.140 264.6);

Tailwind

colors: {
  custom: {
    50: '#6b6fae',
    500: '#1b3a8b',
    950: '#000000',
  },
}

SCSS

$custom: #1b3a8b;
$custom-light: #6b6fae;
$custom-dark: #000000;

JSON

{
  "hex": "#1b3a8b",
  "rgb": {
    "r": 27,
    "g": 58,
    "b": 139
  },
  "hsl": {
    "h": 223.393,
    "s": 67.47,
    "l": 32.549
  },
  "oklch": {
    "l": 0.37869,
    "c": 0.14004,
    "h": 264.6
  },
  "luminance": 0.05123
}

Semantic roles & 50–950 ramp

primary

#1B3A8B

secondary

#BC9B45

accent

#BA3DEA

background

#F6F6FA

surface

#ECECF4

border

#C7C7CE

text

#080710

muted

#7A7A7F

Preview Lab

Preview with #1B3A8B

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

Preview Lab → · Contrast checker → · Palette generator →