International Klein Blue

#001F9B

About International Klein Blue

International Klein Blue, often abbreviated as IKB, is a deep blue hue first mixed by the French artist Yves Klein. Klein registered this color as a trademark in 1957. What makes IKB unique is its remarkable ultramarine depth and intensity. The pigment's formulation involves a synthetic ultramarine pigment suspended in a clear, matte synthetic resin. The visual effect of IKB stems from its capacity to evoke a sense of boundlessness, depth, and a profound emotional response. Yves Klein sought to capture the purest expression of blue, believing it represented the immateriality and vastness of the universe. Its usage continues across diverse artistic and design applications.

The hex color #001f9b, also known as International Klein Blue, presents significant accessibility challenges, especially in web design. Its dark hue results in a low contrast ratio against lighter backgrounds, making text and interactive elements difficult to read for users with visual impairments. To ensure inclusivity, it's crucial to pair this color with very light shades, such as white or very pale yellow, to meet WCAG (Web Content Accessibility Guidelines) standards for contrast. Avoid using #001f9b for extensive blocks of text or essential UI components. Employing color contrast checkers is highly recommended to verify that the contrast ratio meets the minimum requirements for different levels of accessibility compliance. Considering alternative, lighter blues or adjusting the color's luminosity can also improve accessibility while maintaining a similar aesthetic. Remember to test your designs with users who have visual impairments to gather feedback and refine your color choices.

Shades

Digital Color Formats

RGB
0 31 155
RGB0 31 155
Red
Green
Blue
HSL
228 100% 30.39%
22810030.39HSL
Hue
Saturation
Lightness
HWB
228 0% 39.22%
228039.22HWB
Hue
Whiteness
Blackness
hex#001F9B
rgb0 31 155
hsl228 100% 30.39%
cmyk100% 80% 0% 39.22%
hwb228 0% 39.22%
xyz6.41 3.35 31.32
CMYK
100% 80% 0% 39.22%
10080039.22CMYK
Cyan
Magenta
Yellow
Key
XYZ
6.41 3.35 31.32
6.413.3531.32XYZ
X
Y
Z

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