Cobalt Blue color code: #0047AB

An intense pigment blue that reads as pure blue with no grey in it.

Royal Navy
#0047AB

Cobalt Blue · rgb(0, 71, 171)

Every format for Cobalt Blue

HEX
#0047AB
RGB
rgb(0, 71, 171)
HSL
hsl(215, 100%, 34%)
HSV
215°, 100%, 67%
CMYK
100%, 58%, 0%, 33%
Lightness
34% · mid-tone

Hue sits at 215°, which makes Cobalt Blue a slightly cool blue navy, with 100% saturation. In the Royal Navy family it reads as a mid-tone option.

Text contrast on Cobalt Blue

Contrast ratios are calculated using the WCAG 2.1 relative luminance formula. Normal body text needs 4.5:1 and large text needs 3:1 to pass AA.

White text on Cobalt Blue

The quick brown fox jumps over the lazy dog.

8.44:1 — AAA for normal text

Black text on Cobalt Blue

The quick brown fox jumps over the lazy dog.

2.49:1 — below AA, decorative use only

Cobalt Blue text on white

The quick brown fox jumps over the lazy dog.

8.44:1 — AAA for normal text

Accessibility notes

  • Pair Cobalt Blue with white text for the strongest reading experience: that combination gives 8.44:1.
  • Used as a text colour on white, it clears the 3:1 bar for large headings.
  • Never rely on Cobalt Blue alone to communicate state. Add an icon, label or underline so the meaning survives for colour-blind users and in greyscale printing.
  • When placing text over a photograph tinted with Cobalt Blue, add a solid overlay first. Contrast measured against a flat colour does not hold over varying imagery.

Using Cobalt Blue in CSS and HTML

CSS example

:root {
  --cobalt-blue: #0047AB;
}

.panel {
  background-color: var(--cobalt-blue);
  color: #FFFFFF;
  border: 1px solid #0047AB;
}

HTML example

<div style="background-color: #0047AB; color: #FFFFFF; padding: 1rem;">
  Cobalt Blue #0047AB
</div>

Common uses

  • Primary buttons, active navigation states and chart series.
  • Royal Navy palettes for brand systems that need a dependable cool anchor.
  • Print work where a deep blue is preferred to black, using the CMYK build 100%, 58%, 0%, 33%.
  • Data visualisation, as one step in a lightness-based navy scale.

Design recommendations

  • Build lighter and darker variants by changing only the lightness in hsl(215, 100%, 34%). Keeping hue fixed is what makes a scale look intentional.
  • Give Cobalt Blue at least one warm counterweight. A cool palette with no warm accent tends to read as cold rather than calm.
  • Saturation is high here, so use it in measured amounts. Large flat areas of a saturated navy can feel heavy on screen.

Complementary and matching colors

Each of these is derived from the hue, saturation and lightness of Cobalt Blue. Click a swatch to copy it.

Complementary #FF990A
Split complement #FF1F0A
Warm accent #E4C944
Analogous cool #1FECFF
Analogous warm #311FFF
Triadic #EB0062

Similar navy shades

Royal Navy

Royal Navy

HEX
#1E3A8A
RGB
30, 58, 138
HSL
224, 64%, 33%
CMYK
78%, 58%, 0%, 46%

Klein Blue

Royal Navy

HEX
#002FA7
RGB
0, 47, 167
HSL
223, 100%, 33%
CMYK
100%, 72%, 0%, 35%

Zaffre

Royal Navy

HEX
#0014A8
RGB
0, 20, 168
HSL
233, 100%, 33%
CMYK
100%, 88%, 0%, 34%

Egyptian Blue

Royal Navy

HEX
#1034A6
RGB
16, 52, 166
HSL
226, 82%, 36%
CMYK
90%, 69%, 0%, 35%

Yale Blue

Royal Navy

HEX
#0F4D92
RGB
15, 77, 146
HSL
212, 81%, 32%
CMYK
90%, 47%, 0%, 43%

Duke Blue

Royal Navy

HEX
#00009C
RGB
0, 0, 156
HSL
240, 100%, 31%
CMYK
100%, 100%, 0%, 39%

Continue exploring

FAQs about Cobalt Blue

What is the Cobalt Blue color code?

The Cobalt Blue color code is #0047AB in HEX, rgb(0, 71, 171) in RGB and hsl(215, 100%, 34%) in HSL.

What is the RGB value of Cobalt Blue?

Cobalt Blue is rgb(0, 71, 171), meaning 0 units of red, 71 of green and 171 of blue on the 0 to 255 scale.

What is the CMYK value of Cobalt Blue?

In CMYK, Cobalt Blue converts to approximately 100%, 58%, 0%, 33%. Printed output will look slightly less saturated than the screen preview because CMYK covers a narrower gamut.

Does white text work on Cobalt Blue?

White text on Cobalt Blue gives a contrast ratio of 8.44:1, which is AAA for normal text.

Does black text work on Cobalt Blue?

Black text on Cobalt Blue gives a contrast ratio of 2.49:1, which is below AA, decorative use only.

Which colors go with Cobalt Blue?

Its direct complement is #FF990A, and the warm accent #E4C944 works well for calls to action. For a quieter scheme, pair it with the analogous blues listed above.

Is Cobalt Blue a light or dark navy?

At 34% lightness, Cobalt Blue is classed as a mid-tone navy in this collection.