#173F8F#173F8F

#173F8F is a dark, vivid blue. Relative luminance 0.057; OKLCH L 39.1% C 0.140 H 262.1°. Best body text is #FFFFFF at 9.79:1 contrast (WCAG AA passes).

Color values

HEX	#173F8F
RGB	rgb(23, 63, 143)
HSL	hsl(220, 72%, 33%)
HSV	hsv(220, 84%, 56%)
CMYK	cmyk(83.9%, 55.9%, 0%, 43.9%)
CIE-LAB	lab(28.69, 17.80, -48.14)
CIE-LCH	lch(28.69, 51.33, 290.29°)
OKLab	oklab(39.15% -0.0192 -0.139)
OKLCH	oklch(39.15% 0.14 262.1)
XYZ	xyz(7.0870, 5.7195, 26.7117)
Luminance	0.0572 (WCAG relative)
Temperature	cool
Family	blue

Closest named colors

Perceptual scales

Shades

Tints

Tones

OKLCH scale

Color harmonies

complementary

#173F8F #8F6717

analogous

#177B8F #173F8F #2B178F

triadic

#173F8F #8F173F #3F8F17

tetradic

#173F8F #8F177B #8F6717 #178F2B

square

#173F8F #8F177B #8F6717 #178F2B

split-complementary

#173F8F #8F2B17 #7B8F17

monochromatic

#061126 #0F285A #173F8F #1F56C4 #4076E0

Accessibility & contrast

On white

9.79

#173F8F on #FFFFFF

AA ✓AA large ✓AAA ✓

On black

2.14

#173F8F on #000000

AA ✗AA large ✗AAA ✗

Best text color

#FFFFFF on #173F8F

9.79:1 — WCAG AA (normal text) passes

Contrast matrix

fg \ bg	##173F8F	#FFFFFF	#000000	##FFFFFF
##173F8F	1.00	9.79	2.14	9.79
#FFFFFF	9.79	1.00	21.00	1.00
#000000	2.14	21.00	1.00	21.00
##FFFFFF	9.79	1.00	21.00	1.00

Color blindness preview

Protanopia (red-blind)

#004992

Deuteranopia (green-blind)

#003E8D

Tritanopia (blue-blind)

#005360

Achromatopsia (no color)

#444444

Design tokens & code

CSS

--color: #173f8f;
/* rgb */ color: rgb(23, 63, 143);
/* oklch */ color: oklch(39.1% 0.140 262.1);

Tailwind

colors: {
  custom: {
    50: '#6a73b0',
    500: '#173f8f',
    950: '#000000',
  },
}

SCSS

$custom: #173f8f;
$custom-light: #6a73b0;
$custom-dark: #000000;

JSON

{
  "hex": "#173f8f",
  "rgb": {
    "r": 23,
    "g": 63,
    "b": 143
  },
  "hsl": {
    "h": 220,
    "s": 72.289,
    "l": 32.549
  },
  "oklch": {
    "l": 0.39148,
    "c": 0.14028,
    "h": 262.1
  },
  "luminance": 0.0572
}

Semantic roles & 50–950 ramp

primary

#173F8F

secondary

#C19641

accent

#B239EF

background

#F6F6FA

surface

#ECECF5

border

#C7C7CF

text

#080811

muted

#7A7B80

Preview Lab

Preview with #173F8F

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

Preview Lab → · Contrast checker → · Palette generator →