Blue color · XKCD survey name
Ultramarine Color Code: #2000B1
Ultramarine is a medium-dark, vivid blue color with the hexadecimal value #2000B1. In RGB it is 32, 0, 177 and in HSL it is 251°, 100%, 35%. White text reads comfortably on it (12.38:1 contrast).
Ultramarine color values
#2000B1
rgb(32, 0, 177)
hsl(251, 100%, 35%)
251, 100%, 69%
hwb(251 0% 31%)
82%, 100%, 0%, 31%
2097329
CMYK is a standard screen-to-print conversion. Printed results depend on inks, paper and color profiles.
What is Ultramarine?
“Ultramarine” 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 251° places it in the blue part of the color wheel, with 100% saturation (vivid) and 35% lightness (medium-dark). It is a cool color.
Compared with the other blue colors in the Aqeeb Studio library, it is lighter than 23% of them and more saturated than 87% of them.
Its relative luminance is 0.035, 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.
Ultramarine counts as a dark color: its HSL lightness is 35% and its relative luminance is 0.035. White text reads comfortably on it (12.38:1 contrast).
Text contrast on Ultramarine
| Text | Preview | Ratio | AA normal | AA large | AAA normal | AAA large |
|---|---|---|---|---|---|---|
| White text | Sample text | 12.38:1 Excellent | Pass | Pass | Pass | Pass |
| Black text | Sample text | 1.69:1 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 Ultramarine
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.
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.
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.
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.
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.
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.
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 Ultramarine
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.
Similar colors
Where to use Ultramarine
- Button, banner and badge backgrounds with white text (12.38:1 contrast)
- Accents that need to stand out: call-to-action buttons, charts and illustrations
- Links, buttons and primary interface accents
- Corporate, finance and software branding
- Headers and navigation bars
- Charts and dashboards
Use Ultramarine in CSS
:root {
--color-ultramarine: #2000B1;
}
.element {
color: var(--color-ultramarine);
background-color: #2000B1;
border: 2px solid #2000B1;
}Questions about Ultramarine
What is the HEX code for Ultramarine?
Ultramarine is #2000B1.
What is the RGB value of Ultramarine?
The RGB value of Ultramarine is 32, 0, 177: 32 red, 0 green and 177 blue on a 0–255 scale, written rgb(32, 0, 177) in CSS.
What is the HSL value of Ultramarine?
The HSL value of Ultramarine is 251°, 100%, 35% (hue, saturation, lightness), written hsl(251, 100%, 35%) in CSS.
What is the CMYK value of Ultramarine?
A standard conversion gives about C 82%, M 100%, Y 0%, K 31%. Real print results depend on the inks, paper and color profile, so treat CMYK here as a reference value.
Is Ultramarine a light or dark color?
Ultramarine counts as a dark color: its HSL lightness is 35% and its relative luminance is 0.035. White text reads comfortably on it (12.38:1 contrast).
How does Ultramarine look with white text?
White text on Ultramarine has a contrast ratio of 12.38:1, rated Excellent. It meets WCAG AA for normal text.
How does Ultramarine look with black text?
Black text on Ultramarine has a contrast ratio of 1.69:1, rated Poor. It falls below the WCAG minimum for text.
What colors go well with Ultramarine?
Bright Olive is its complementary color, and Sapphire sits beside it as an analogous color. Lighter and darker variants of the same hue also work well for monochromatic palettes.
Where can Ultramarine be used?
It suits button, banner and badge backgrounds with white text (12.38:1 contrast); accents that need to stand out: call-to-action buttons, charts and illustrations; links, buttons and primary interface accents.
How do I use Ultramarine in CSS?
Use color: #2000B1; for text, background-color: #2000B1; for fills, or define a custom property such as --color-ultramarine: #2000B1; and reuse it with var(--color-ultramarine).
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.