International Klein Blue

#031FBA

General Information about International Klein Blue

International Klein Blue, often abbreviated as IKB, is a deep blue hue first mixed by the French artist Yves Klein. This vivid ultramarine color was specifically developed by Klein in collaboration with a Parisian paint supplier, Édouard Adam, to visually capture the depth and intensity of the color without losing its original qualities and intensity from the pigment. IKB is renowned for its matte finish, which contributes to its remarkable luminosity and makes it appear almost velvety. Yves Klein patented IKB in 1957, though the patent refers to the formula for the paint, not the color itself.

The hex color #031FBA, also known as International Klein Blue, presents some accessibility challenges, especially in web design. Its very dark hue results in low contrast when paired with similarly dark colors. This low contrast can make text and other elements difficult to read for users with visual impairments, including those with low vision or color blindness. To ensure accessibility, it is crucial to use #031FBA with light colors, such as white or very pale yellows, to achieve a sufficient contrast ratio as defined by WCAG guidelines. A contrast ratio of at least 4.5:1 for normal text and 3:1 for large text is recommended. Furthermore, avoid using #031FBA as the sole indicator of important information; instead, provide alternative cues such as text labels or icons.

Shades

Digital Color Formats

RGB
3 31 186
RGB3 31 186
Red
Green
Blue
HSL
230.82deg 96.83% 37.06%
230.8296.8337.06HSL
Hue
Saturation
Lightness
HWB
230.82deg 1.18% 27.06%
230.821.1827.06HWB
Hue
Whiteness
Blackness
hex#031FBA
rgb3 31 186
hsl230.82deg 96.83% 37.06%
cmyk98.39% 83.33% 0% 27.06%
hwb230.82deg 1.18% 27.06%
xyz-d650.09 0.05 0.47
oklch0.3793 0.2318 264.54
oklab0.3793 -0.02 -0.23
CMYK
98.39% 83.33% 0% 27.06%
98.3983.33027.06CMYK
Cyan
Magenta
Yellow
Key
XYZ-d65
0.09 0.05 0.47
0.090.050.47XYZ
X
Y
Z
OKLCH
0.3793 0.2318 264.54
0.37930.2318264.54LCH
Lightness
Chroma
Hue
OKLAB
0.3793 -0.02 -0.23
0.3793-0.02-0.23LAB
Lightness
Green-Red
Blue-Yellow

Alternative colors

Applications

Complementary color

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