Blue #0000FF colour

#0000FF is the CSS colour blue. RGB 0, 0, 255, HSL 240, 100%, 50%. White text passes AAA (8.59:1), black fails (2.44:1). Tints, shades and palettes.

#0000FF

CSS name: blue, one of the 16 original HTML colours
Nearest other: mediumblue #0000cd
Described as: a vivid blue
Red, green, blue: 0, 0, 255
Web safe: Yes, one of the 216 web-safe colours
Luminance: 0.0722 (WCAG relative luminance, 0 is black, 1 is white)

Colour codes

HEX	`#0000ff`
HEX (short)	`#00f`
RGB	`rgb(0, 0, 255)`
RGB (percent)	`rgb(0% 0% 100%)`
HSL	`hsl(240, 100%, 50%)`
HSV / HSB	`hsv(240, 100%, 100%)`
HWB	`hwb(240 0% 0%)`
CMYK (naive)	`cmyk(100%, 100%, 0%, 0%)`
CIELAB (D50)	`lab(29.57% 68.29 -112.02)`
OKLCH	`oklch(45.2% 0.3132 264.05)`
Decimal	`255`

CMYK here is the plain formula with no colour profile, so treat it as a starting point; a printer's profile gives the real ink values. CIELAB uses a D50 white point, as CSS lab() does. HSV is not a CSS function, so it is shown for design apps only.

Contrast with white and black text

White text, 8.59:1The quick brown fox jumps over the lazy dog.

Black text, 2.44:1The quick brown fox jumps over the lazy dog.

Text	Ratio	AA normal (4.5)	AA large (3)	AAA normal (7)	AAA large (4.5)
White	8.59:1	Pass	Pass	Pass	Pass
Black	2.44:1	Fail	Fail	Fail	Fail

White text is the better choice on #0000FF (8.59:1). Ratios use the WCAG 2.2 formula; large text means at least 24px, or 18.66px bold. Check another pair.

Tints and shades

Mixed with white, then with black, in ten even steps (straight sRGB mixing, as most design tools do).

9%#1717ff 18%#2e2eff 27%#4646ff 36%#5d5dff 45%#7474ff 55%#8b8bff 64%#a2a2ff 73%#b9b9ff 82%#d1d1ff 91%#e8e8ff

9%#0000e8 18%#0000d1 27%#0000b9 36%#0000a2 45%#00008b 55%#000074 64%#00005d 73%#000046 82%#00002e 91%#000017

Colour harmonies

Hue turned around the HSL colour wheel, saturation and lightness kept.

Complementary

The hue opposite on the colour wheel (180°).

#0000ff #ffff00

Analogous

Neighbours 30° either side.

#0080ff #0000ff #8000ff

Triadic

Three hues 120° apart.

#0000ff #ff0000 #00ff00

Split complementary

The two hues either side of the complement (150° and 210°).

#0000ff #ff8000 #80ff00

Tetradic (square)

Four hues 90° apart.

#0000ff #ff0080 #ffff00 #00ff80

How it looks with colour blindness

Normal vision#0000ff Protanopia#0059ff Deuteranopia#003dfb Tritanopia#006b96 Achromatopsia#4c4c4c

Simulated with the Machado, Oliveira and Fernandes (2009) matrices at full severity, applied in linear RGB; achromatopsia shows the colour's luminance as grey. Milder forms (protanomaly, deuteranomaly) are far more common and shift colours less. Never use colour as the only way to carry meaning.

CSS

Text colour	`color: #0000ff;`
Background	`background-color: #0000ff;`
Border	`border: 1px solid #0000ff;`
Half transparent	`background-color: rgb(0 0 255 / 50%);`
Custom property	`--colour-main: #0000ff;`
Gradient to a darker shade	`background: linear-gradient(135deg, #0000ff, #000099);`
Gradient from a lighter tint	`background: linear-gradient(180deg, #6666ff, #0000ff);`
Text on this colour	`background-color: #0000ff; color: #fff;`

Similar named colours

Distance is measured in OKLab, scaled by 100; under about 2 is hard to tell apart side by side.

Convert #0000FF to other formats · Build a palette from it · Check contrast · All named colours

Colour names from CSS Color Module Level 4. Palette values from the Tailwind CSS v3 default palette (MIT licence) and the Material Design 2014 colour palette as published in Material Design Lite (Apache License 2.0). All other values are calculated from the hex code.