Blue Charcoal

#000A21

General Information about Blue Charcoal (#000A21)

The color #000A21, also known as Blue Charcoal, is a very dark shade of blue. It belongs to the blue color family but is substantially muted, giving it a charcoal-like appearance. In the RGB color model, it is composed of 0 red, 10 green, and 33 blue. In the CMYK color model, used primarily for printing, it consists of 100% cyan, 69.7% magenta, 0% yellow, and 87.1% black. This color is often associated with feelings of sophistication, depth, and mystery. Its low saturation makes it a versatile choice for backgrounds and accents in various design applications, where it can provide a subtle yet impactful presence. Due to its darkness, it's crucial to consider contrast ratios when using this color in web design to ensure accessibility standards are met.

The hex color #000A21, often referred to as Blue Charcoal, presents certain accessibility challenges, particularly in web design. Its very low luminance value means that text or other elements using this color as a background require extremely light foreground colors to ensure sufficient contrast. According to WCAG guidelines, a contrast ratio of at least 4.5:1 is necessary for normal-sized text and 3:1 for large text to meet Level AA compliance. When using #000A21, careful consideration must be given to the foreground color choice. Using online contrast checkers can help web developers ensure that the selected color combinations meet the required accessibility standards. Failure to provide adequate contrast can result in content that is unreadable or difficult to perceive for users with visual impairments, including those with low vision or color blindness. It is advisable to pair #000A21 with colors like #FFFFFF (white) or very light shades of gray to maximize readability and accessibility.

Shades

Digital Color Formats

RGB
0 10 33
RGB0 10 33
Red
Green
Blue
HSL
221.82 100% 6.47%
221.821006.47HSL
Hue
Saturation
Lightness
HWB
221.82 0% 87.06%
221.82087.06HWB
Hue
Whiteness
Blackness
hex#000A21
rgb0 10 33
hsl221.82 100% 6.47%
cmyk100% 69.7% 0% 87.06%
hwb221.82 0% 87.06%
xyz0.38 0.33 1.48
CMYK
100% 69.7% 0% 87.06%
10069.7087.06CMYK
Cyan
Magenta
Yellow
Key
XYZ
0.38 0.33 1.48
0.380.331.48XYZ
X
Y
Z

Alternative colors

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