International Klein Blue

#0123B3

General Information about International Klein Blue

The hex color #0123b3, also known as International Klein Blue or IKB, is a deep, saturated blue color known for its striking intensity. Developed by the French artist Yves Klein in collaboration with a Parisian paint supplier, this particular shade of blue was intended to convey the purest expression of blue, representing the boundless and immaterial aspects of reality. Klein registered IKB as a trademark in 1957, solidifying its status as a unique and recognizable color. In the RGB color model, #0123b3 is composed of 0.4% red, 13.7% green, and 70.2% blue. It is a dark color with a relatively low lightness value. IKB's unique vibrancy makes it popular in art, fashion, and design, where it is used to create a bold and impactful visual statement.

The hex color #0123b3, a deep and vibrant blue reminiscent of International Klein Blue, presents some accessibility challenges, especially when used as a primary color for text or interactive elements. Its low lightness value (around 7%) means that it requires very light text (white or near-white) to achieve sufficient contrast for readability, meeting WCAG standards. Otherwise, users with visual impairments may struggle to distinguish text from the background. When used for backgrounds or larger design elements, consider pairing it with lighter complementary colors like #b2dfff or #ffe6cc to increase overall contrast, ensuring that interactive elements like buttons and links are easily identifiable. It is crucial to use an automated color contrast checker to make sure the contrast ratio is at least 4.5:1 for normal text and 3:1 for large text, adhering to WCAG AA guidelines, and even higher (7:1 and 4.5:1, respectively) for AAA compliance. Also, remember that color should not be the only visual means of conveying information. Using icons, underlines, or patterns can help individuals with color blindness perceive differences.

Shades

Digital Color Formats

RGB
1 35 179
RGB1 35 179
Red
Green
Blue
HSL
228.54 98.89% 35.29%
228.5498.8935.29HSL
Hue
Saturation
Lightness
HWB
228.54 0.39% 29.8%
228.540.3929.8HWB
Hue
Whiteness
Blackness
hex#0123B3
rgb1 35 179
hsl228.54 98.89% 35.29%
cmyk99.44% 80.45% 0% 29.8%
hwb228.54 0.39% 29.8%
xyz8.75 4.46 43.05
CMYK
99.44% 80.45% 0% 29.8%
99.4480.45029.8CMYK
Cyan
Magenta
Yellow
Key
XYZ
8.75 4.46 43.05
8.754.4643.05XYZ
X
Y
Z

Alternative colors

Applications

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