#173A8B#173A8B

#173A8B is a dark, vivid blue. Relative luminance 0.051; OKLCH L 37.7% C 0.141 H 263.5°. Best body text is #FFFFFF at 10.42:1 contrast (WCAG AA passes).

Color values

HEX	#173A8B
RGB	rgb(23, 58, 139)
HSL	hsl(222, 72%, 32%)
HSV	hsv(222, 83%, 55%)
CMYK	cmyk(83.5%, 58.3%, 0%, 45.5%)
CIE-LAB	lab(26.94, 19.65, -48.53)
CIE-LCH	lch(26.94, 52.36, 292.05°)
OKLab	oklab(37.72% -0.0161 -0.1402)
OKLCH	oklch(37.72% 0.141 263.5)
XYZ	xyz(6.5249, 5.0716, 25.0561)
Luminance	0.0507 (WCAG relative)
Temperature	cool
Family	blue

Closest named colors

Perceptual scales

Shades

Tints

Tones

OKLCH scale

Color harmonies

complementary

#173A8B #8B6817

analogous

#17748B #173A8B #2E178B

triadic

#173A8B #8B173A #3A8B17

tetradic

#173A8B #8B1774 #8B6817 #178B2E

square

#173A8B #8B1774 #8B6817 #178B2E

split-complementary

#173A8B #8B2E17 #748B17

monochromatic

#060E22 #0E2456 #173A8B #2050C0 #3D6EDF

Accessibility & contrast

On white

10.42

#173A8B on #FFFFFF

AA ✓AA large ✓AAA ✓

On black

2.01

#173A8B on #000000

AA ✗AA large ✗AAA ✗

Best text color

#FFFFFF on #173A8B

10.42:1 — WCAG AA (normal text) passes

Contrast matrix

fg \ bg	##173A8B	#FFFFFF	#000000	##FFFFFF
##173A8B	1.00	10.42	2.01	10.42
#FFFFFF	10.42	1.00	21.00	1.00
#000000	2.01	21.00	1.00	21.00
##FFFFFF	10.42	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: #173a8b;
/* rgb */ color: rgb(23, 58, 139);
/* oklch */ color: oklch(37.7% 0.141 263.5);

Tailwind

colors: {
  custom: {
    50: '#6a6fae',
    500: '#173a8b',
    950: '#000000',
  },
}

SCSS

$custom: #173a8b;
$custom-light: #6a6fae;
$custom-dark: #000000;

JSON

{
  "hex": "#173a8b",
  "rgb": {
    "r": 23,
    "g": 58,
    "b": 139
  },
  "hsl": {
    "h": 221.897,
    "s": 71.605,
    "l": 31.765
  },
  "oklch": {
    "l": 0.37721,
    "c": 0.14111,
    "h": 263.5
  },
  "luminance": 0.05072
}

Semantic roles & 50–950 ramp

primary

#173A8B

secondary

#BF983F

accent

#B839EE

background

#F6F6FA

surface

#ECECF4

border

#C7C7CE

text

#070710

muted

#7A7A7F

Preview Lab

Preview with #173A8B

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

Preview Lab → · Contrast checker → · Palette generator →