International Klein Blue

#051DAF

About International Klein Blue

International Klein Blue, often referred to as IKB, is a deep blue hue first mixed by the French artist Yves Klein. This specific shade was developed in collaboration with a Parisian paint dealer, Edouard Adam, to perfectly capture and maintain the color intensity and visual impact that Klein sought in his monochrome paintings. Its unique characteristic lies in its matte finish, which enhances the color's saturation and vibrancy by eliminating reflective glare. Klein patented IKB in 1957, ensuring its recognition and preservation. Chemically, it is created using a synthetic ultramarine pigment suspended in a polyvinyl acetate binder. Its intense depth and purity have made it a prominent color in art, fashion, and design, often associated with concepts of freedom, infinity, and spirituality.

The color #051DAF, also known as International Klein Blue, presents significant accessibility challenges, especially in web design. Its very low luminance value (making it a dark color) means that using it as a background color requires very light text to ensure sufficient contrast. According to WCAG guidelines, the contrast ratio between text and background should be at least 4.5:1 for normal text and 3:1 for large text to meet AA compliance. Given the darkness of #051DAF, achieving this contrast may necessitate using almost white text. Moreover, colorblind users, especially those with tritanopia or deuteranopia, might perceive this blue differently, potentially reducing contrast further. Therefore, careful consideration and testing with accessibility tools are crucial when incorporating this color into designs to ensure readability and usability for all users. Providing alternative color schemes or allowing users to adjust the color settings can greatly improve the accessibility of content using this intense blue.

Shades

Digital Color Formats

RGB
5 29 175
RGB5 29 175
Red
Green
Blue
HSL
231.53 94.44% 35.29%
231.5394.4435.29HSL
Hue
Saturation
Lightness
HWB
231.53 1.96% 31.37%
231.531.9631.37HWB
Hue
Whiteness
Blackness
hex#051DAF
rgb5 29 175
hsl231.53 94.44% 35.29%
cmyk97.14% 83.43% 0% 31.37%
hwb231.53 1.96% 31.37%
xyz8.24 4.01 40.9
CMYK
97.14% 83.43% 0% 31.37%
97.1483.43031.37CMYK
Cyan
Magenta
Yellow
Key
XYZ
8.24 4.01 40.9
8.244.0140.9XYZ
X
Y
Z

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