International Klein Blue

#042CB0

About International Klein Blue

International Klein Blue, also known as IKB, is a deep blue hue that was developed by the French artist Yves Klein. Its unique vividness and intensity are achieved through a specific formulation using a synthetic ultramarine pigment. Klein registered this color as a trademark to protect its unique identity and connection to his artistic work. It is valued for its ability to evoke feelings of depth, infinity, and spirituality. The color has found its place not only in fine arts, but also in design, fashion, and various commercial applications. It continues to inspire artists and designers seeking to create impactful and visually striking works.

International Klein Blue (#042CB0) exhibits a strong blue hue with very low luminance, posing significant accessibility challenges, especially for users with visual impairments. The contrast ratio against a white background is extremely low, making text and other interface elements nearly unreadable. To ensure accessibility, it is crucial to avoid using this color for text or interactive elements without careful consideration. When used, it should be paired with very light colors such as white or very pale yellow to meet WCAG (Web Content Accessibility Guidelines) AA or AAA standards. Additionally, providing alternative cues like icons or text labels can further enhance usability for individuals with color vision deficiencies. A minimum contrast ratio of 4.5:1 for normal text and 3:1 for large text is recommended to achieve WCAG compliance. This can be verified with online contrast checker tools.

Shades

Digital Color Formats

RGB
4 44 176
RGB4 44 176
Red
Green
Blue
HSL
226.05deg 95.56% 35.29%
226.0595.5635.29HSL
Hue
Saturation
Lightness
HWB
226.05deg 1.57% 30.98%
226.051.5730.98HWB
Hue
Whiteness
Blackness
hex#042CB0
rgb4 44 176
hsl226.05deg 95.56% 35.29%
cmyk97.73% 75% 0% 30.98%
hwb226.05deg 1.57% 30.98%
xyz-d650.09 0.05 0.42
oklch0.3846 0.2089 264.15
oklab0.3846 -0.02 -0.21
CMYK
97.73% 75% 0% 30.98%
97.7375030.98CMYK
Cyan
Magenta
Yellow
Key
XYZ-d65
0.09 0.05 0.42
0.090.050.42XYZ
X
Y
Z
OKLCH
0.3846 0.2089 264.15
0.38460.2089264.15LCH
Lightness
Chroma
Hue
OKLAB
0.3846 -0.02 -0.21
0.3846-0.02-0.21LAB
Lightness
Green-Red
Blue-Yellow

Alternative colors

Applications

Complementary color

Buttons