Home·Colour name reference

Cobalt blue

#0047AB

HEX#0047AB
RGB0, 71, 171
HSL215°, 100%, 34%
CMYK100%, 58%, 0%, 33%
Relative luminance0.07

Text contrast

Aa

On white

8.44:1 Passes AA

Aa

On black

2.49:1 Below AA

Colours that work with it

Complement

#AD6500

Analogous

#009FAD#0E00AD

Triadic

#AD0048#48AD00

Shade scale

50100200300400500600700800

Seen with colour blindness

ProtanopiaDeuteranopiaTritanopia

How to read this

  • A hex code writes red, green and blue as two hexadecimal digits each. #ff0000 is red at full strength and the others at zero.
  • HSL states hue (0–360°), saturation and lightness. Nudging a colour brighter means changing one number, which is why it is easier to work with by hand.
  • Text contrast follows WCAG. Body-size text needs 4.5:1 or better, and 21:1 between white and black is the maximum possible.
  • The colour-blindness row computes how this colour appears under three types of colour vision deficiency — the reason never to encode information in colour alone.

Frequently asked questions

Q. What is the hex code for Cobalt blue?

#0047AB. That is 0, 71, 171 in RGB, and hue 215°, saturation 100%, lightness 34% in HSL.

Q. Should text on Cobalt blue be white or black?

White. Contrast against white is 8.44:1 and against black 2.49:1, so take the higher one if body-size text has to be readable.

Q. What is the complement of Cobalt blue?

#AD6500, sitting 180° across the colour wheel. Side by side the two push against each other hardest, which makes it a good accent but tiring over large areas.

Q. Can I send these CMYK values straight to print?

The computed values are C 100% · M 58% · Y 0% · K 33%. Real printing depends on paper and ink, so check against the printer's swatch book when the colour matters.

Q. Is this colour distinguishable with colour blindness?

It appears as #1F1F93 with protanopia, #1B158D with deuteranopia and #04807C with tritanopia. Where those values converge with another colour, add a shape or a label instead of relying on hue.

Nearby colours