Cobalt Blue Color Code: #030AA7, RGB & HSL

Cobalt Blue color values

HEX #030AA7

RGB rgb(3, 10, 167)

HSL hsl(237, 96%, 33%)

HSV 237, 98%, 65%

HWB hwb(237 1% 35%)

CMYK 98%, 94%, 0%, 35%

Decimal 199335

33%HSL lightness (medium-dark)

96%HSL saturation (vivid)

237°Hue angle (blue)

0.030Relative luminance

CMYK is a standard screen-to-print conversion. Printed results depend on inks, paper and color profiles.

What is Cobalt Blue?

“Cobalt Blue” is a crowd-sourced name from the XKCD Color Survey, in which participants typed names for colors they were shown. It is a popular everyday label rather than an official standard.

Its hue angle of 237° places it in the blue part of the color wheel, with 96% saturation (vivid) and 33% lightness (medium-dark). It is a cool color.

Compared with the other blue colors in the Aqeeb Studio library, it is lighter than 21% of them and more saturated than 62% of them.

Its relative luminance is 0.030, which makes it a dark color. That is below the 0.179 crossover point at which black and white text have equal contrast, so white text has the advantage.

Cobalt Blue counts as a dark color: its HSL lightness is 33% and its relative luminance is 0.030. White text reads comfortably on it (13.08:1 contrast).

Text contrast on Cobalt Blue

WCAG contrast of white and black text on Cobalt Blue
Text	Preview	Ratio	AA normal	AA large	AAA normal	AAA large
White text	Sample text	13.08:1 Excellent	Pass	Pass	Pass	Pass
Black text	Sample text	1.60:1 Poor	Fail	Fail	Fail	Fail

Ratios use the WCAG 2 formula and are truncated, never rounded up. Test any pair with the contrast checker.

Colors that go with Cobalt Blue

Complementary color

Complementary colors sit directly opposite each other on the color wheel (180° apart). They give the strongest hue contrast, which suits calls to action and accents.

≈ Brown Yellow#A7A003

Analogous colors

Analogous colors are neighbors on the wheel, 30° either side of the base hue. They blend smoothly and are easy to combine in backgrounds, gradients and illustrations.

≈ Mid Blue#035CA7 ≈ Indigo Blue#4E03A7

Triadic colors

A triadic scheme uses three hues spaced 120° apart. It is lively yet balanced, and works best when one color leads and the other two act as accents.

≈ Deep Red#A7030A ≈ Kelly Green#0AA703

Split-complementary colors

Split-complementary keeps the base color and uses the two colors on either side of its complement (150° and 210°). The contrast is strong but gentler than a direct complement.

≈ Cinnamon#A74E03 ≈ Leaf Green#5CA703

Tetradic colors

A tetradic (rectangle) scheme combines two complementary pairs at 0°, 60°, 180° and 240°. It offers variety but needs one dominant color to stay balanced.

≈ Dark Magenta#A003A7 ≈ Brown Yellow#A7A003 ≈ Kelly Green#0AA703

Monochromatic variants

Monochromatic variants keep the same hue and saturation and only change lightness, which makes them dependable for UI scales and subtle layered designs.

#01021E#01021E

#020664#020664

#030AAA#030AAA

#040EF0#040EF0

#4149FC#4149FC

A “≈” before a name means the exact harmony color has no named match, so the link goes to the closest named color.

Tints and shades of Cobalt Blue

Lighter tints (mixed with white)

Darker shades (mixed with black)

Select any swatch to copy its HEX code. Build longer scales with the tints and shades tool.

Ultramarine#2000B1 Indigo Blue#3A18B1 Dark Blue#00008B Blue Purple#5729CE Royal#0C1793 Violet Blue#510AC9 Navy#000080 True Blue#010FCC

Where to use Cobalt Blue

Button, banner and badge backgrounds with white text (13.08:1 contrast)
Accents that need to stand out: call-to-action buttons, charts and illustrations
Charts and dashboards
Links, buttons and primary interface accents
Corporate, finance and software branding
Headers and navigation bars

Use Cobalt Blue in CSS

:root {
  --color-cobalt-blue: #030AA7;
}

.element {
  color: var(--color-cobalt-blue);
  background-color: #030AA7;
  border: 2px solid #030AA7;
}

Questions about Cobalt Blue

What is the HEX code for Cobalt Blue?

Cobalt Blue is #030AA7.

What is the RGB value of Cobalt Blue?

The RGB value of Cobalt Blue is 3, 10, 167: 3 red, 10 green and 167 blue on a 0–255 scale, written rgb(3, 10, 167) in CSS.

What is the HSL value of Cobalt Blue?

The HSL value of Cobalt Blue is 237°, 96%, 33% (hue, saturation, lightness), written hsl(237, 96%, 33%) in CSS.

What is the CMYK value of Cobalt Blue?

A standard conversion gives about C 98%, M 94%, Y 0%, K 35%. Real print results depend on the inks, paper and color profile, so treat CMYK here as a reference value.

Is Cobalt Blue a light or dark color?

Cobalt Blue counts as a dark color: its HSL lightness is 33% and its relative luminance is 0.030. White text reads comfortably on it (13.08:1 contrast).

How does Cobalt Blue look with white text?

White text on Cobalt Blue has a contrast ratio of 13.08:1, rated Excellent. It meets WCAG AA for normal text.

How does Cobalt Blue look with black text?

Black text on Cobalt Blue has a contrast ratio of 1.60:1, rated Poor. It falls below the WCAG minimum for text.

What colors go well with Cobalt Blue?

Brown Yellow is its complementary color, and Mid Blue sits beside it as an analogous color. Lighter and darker variants of the same hue also work well for monochromatic palettes.

Where can Cobalt Blue be used?

It suits button, banner and badge backgrounds with white text (13.08:1 contrast); accents that need to stand out: call-to-action buttons, charts and illustrations; charts and dashboards.

How do I use Cobalt Blue in CSS?

Use color: #030AA7; for text, background-color: #030AA7; for fills, or define a custom property such as --color-cobalt-blue: #030AA7; and reuse it with var(--color-cobalt-blue).

About this color page

Crowd-sourced name from the XKCD Color Survey (CC0). Values are calculated from the HEX code; color names are labels, not trademarks or standards unless stated. Screens render colors differently, so always check important colors on your own device. See the disclaimer.

Cobalt Blue Color Code: #030AA7