International Klein Blue

#0521AF

About International Klein Blue

International Klein Blue, often abbreviated as IKB, is a deep blue hue first mixed by the French artist Yves Klein. The color's visual effect comes from its heavy reliance on ultramarine pigment, and Klein registered this mixture as a trademark in 1957. IKB's unique and vibrant quality arises from the ultramarine pigment's purity and intensity, often described as having an almost hypnotic effect on viewers. The color has found a place in various fields, including art, fashion, and design, prized for its distinctiveness and the sense of depth and emotion it evokes. The intense saturation and dark undertones make it a compelling choice for those seeking to make a bold statement.

The hex color #0521af, known as International Klein Blue, presents significant accessibility challenges, particularly in web design. Its extremely low luminance value of 0.01 means that text or elements using this color as a background will require very light foreground colors to meet WCAG (Web Content Accessibility Guidelines) standards for contrast. A contrast ratio of at least 4.5:1 is recommended for normal text and 3:1 for large text to ensure readability for users with visual impairments. Using #0521af for crucial UI elements without proper contrast can exclude users with low vision or color blindness. Careful consideration and testing with accessibility tools are essential when implementing this color to ensure inclusivity and a positive user experience. Ensure sufficient contrast by pairing this dark blue with colors like white or light yellow.

Shades

Digital Color Formats

RGB
5 33 175
RGB5 33 175
Red
Green
Blue
HSL
230.12 94.44% 35.29%
230.1294.4435.29HSL
Hue
Saturation
Lightness
HWB
230.12 1.96% 31.37%
230.121.9631.37HWB
Hue
Whiteness
Blackness
hex#0521AF
rgb5 33 175
hsl230.12 94.44% 35.29%
cmyk97.14% 81.14% 0% 31.37%
hwb230.12 1.96% 31.37%
xyz8.34 4.22 40.93
CMYK
97.14% 81.14% 0% 31.37%
97.1481.14031.37CMYK
Cyan
Magenta
Yellow
Key
XYZ
8.34 4.22 40.93
8.344.2240.93XYZ
X
Y
Z

Alternative colors

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