#1F428B#1F428B

#1F428B is a dark, vivid blue. Relative luminance 0.061; OKLCH L 39.8% C 0.128 H 262.7°. Best body text is #FFFFFF at 9.50:1 contrast (WCAG AA passes).

Color values

HEX	#1F428B
RGB	rgb(31, 66, 139)
HSL	hsl(221, 64%, 33%)
HSV	hsv(221, 78%, 55%)
CMYK	cmyk(77.7%, 52.5%, 0%, 45.5%)
CIE-LAB	lab(29.54, 14.99, -44.29)
CIE-LCH	lch(29.54, 46.76, 288.69°)
OKLab	oklab(39.77% -0.0162 -0.1274)
OKLCH	oklch(39.77% 0.128 262.7)
XYZ	xyz(7.1718, 6.0510, 25.2111)
Luminance	0.0605 (WCAG relative)
Temperature	cool
Family	blue

Closest named colors

Perceptual scales

Shades

Tints

Tones

OKLCH scale

Color harmonies

complementary

#1F428B #8B681F

analogous

#1F788B #1F428B #321F8B

triadic

#1F428B #8B1F42 #428B1F

tetradic

#1F428B #8B1F78 #8B681F #1F8B32

square

#1F428B #8B1F78 #8B681F #1F8B32

split-complementary

#1F428B #8B321F #788B1F

monochromatic

#091227 #142A59 #1F428B #2A5ABD #4D7AD7

Accessibility & contrast

On white

9.50

#1F428B on #FFFFFF

AA ✓AA large ✓AAA ✓

On black

2.21

#1F428B on #000000

AA ✗AA large ✗AAA ✗

Best text color

#FFFFFF on #1F428B

9.50:1 — WCAG AA (normal text) passes

Contrast matrix

fg \ bg	##1F428B	#FFFFFF	#000000	##FFFFFF
##1F428B	1.00	9.50	2.21	9.50
#FFFFFF	9.50	1.00	21.00	1.00
#000000	2.21	21.00	1.00	21.00
##FFFFFF	9.50	1.00	21.00	1.00

Color blindness preview

Protanopia (red-blind)

#134B8E

Deuteranopia (green-blind)

#00418A

Tritanopia (blue-blind)

#005460

Achromatopsia (no color)

#464646

Design tokens & code

CSS

--color: #1f428b;
/* rgb */ color: rgb(31, 66, 139);
/* oklch */ color: oklch(39.8% 0.128 262.7);

Tailwind

colors: {
  custom: {
    50: '#6b75ad',
    500: '#1f428b',
    950: '#000000',
  },
}

SCSS

$custom: #1f428b;
$custom-light: #6b75ad;
$custom-dark: #000000;

JSON

{
  "hex": "#1f428b",
  "rgb": {
    "r": 31,
    "g": 66,
    "b": 139
  },
  "hsl": {
    "h": 220.556,
    "s": 63.529,
    "l": 33.333
  },
  "oklch": {
    "l": 0.39774,
    "c": 0.12848,
    "h": 262.7
  },
  "luminance": 0.06052
}

Semantic roles & 50–950 ramp

primary

#1F428B

secondary

#BA964C

accent

#B141E7

background

#F6F7FA

surface

#ECEDF4

border

#C7C8CE

text

#080810

muted

#7A7B7F

Preview Lab

Preview with #1F428B

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

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