Ultramarine

#21009B

General Information about #21009B

The hexadecimal color code #21009B represents a dark shade of blue-violet in the RGB color model. It is composed of 12.9% red, 0% green, and 61.2% blue. In the CMYK color model, it consists of 79% cyan, 100% magenta, 0% yellow, and 39% black. This color is often referred to as ultramarine, which is known for its depth and richness. It is associated with qualities such as wisdom, trust, and intelligence. Historically, ultramarine pigment was derived from the precious stone lapis lazuli, making it a highly valued and expensive color. The digital representation of this color allows for its accessibility and use across various media and applications, from web design to digital art.

The color #21009B, a deep shade of ultramarine, presents some accessibility challenges. Its dark nature means it needs to be paired with very light text (ideally white or a very pale yellow) to ensure sufficient contrast for readability. Using a color contrast checker is highly recommended to meet WCAG guidelines, aiming for a contrast ratio of at least 4.5:1 for normal text and 3:1 for large text. When used for interactive elements like buttons or links, ensure that hover and focus states also maintain adequate contrast. Avoid using this color for small or intricate icons, as its darkness can obscure details. Also, be mindful of users with visual impairments; providing alternative cues, such as underlines for links or labels for form fields, can improve accessibility. For complex data visualizations, use this color sparingly, opting for lighter and more distinguishable hues for better clarity.

Shades

Digital Color Formats

RGB
33 0 155
RGB33 0 155
Red
Green
Blue
HSL
252.77 100% 30.39%
252.7710030.39HSL
Hue
Saturation
Lightness
HWB
252.77 0% 39.22%
252.77039.22HWB
Hue
Whiteness
Blackness
hex#21009B
rgb33 0 155
hsl252.77 100% 30.39%
cmyk78.71% 100% 0% 39.22%
hwb252.77 0% 39.22%
xyz6.54 2.69 31.18
CMYK
78.71% 100% 0% 39.22%
78.71100039.22CMYK
Cyan
Magenta
Yellow
Key
XYZ
6.54 2.69 31.18
6.542.6931.18XYZ
X
Y
Z

Alternative colors

Applications

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