International Klein Blue

#0133B3

About International Klein Blue

International Klein Blue (IKB), also known as #0133B3, is a deep blue hue first mixed by the French artist Yves Klein. Klein registered this color as a trademark in 1957, even though it wasn't patentable under French law. IKB's visual impact comes from its intense saturation achieved through a specific formula that involves suspending pure ultramarine pigment in a synthetic resin. This resin allows the pigment to maintain its vibrancy and minimizes the loss of brilliance that can occur with traditional binders. The color is known for its unique matte finish, which enhances its light-absorbing qualities, creating a sense of depth and infinity. The color is a symbol of modern art and visual expression.

The hex color #0133B3, or International Klein Blue, presents some accessibility challenges, particularly in web design. Its dark hue means that careful consideration must be given to the color of text and interactive elements placed on a background of this color. To ensure readability and usability, it's crucial to use light-colored text, such as white or very pale shades of yellow or green, with a contrast ratio that meets WCAG (Web Content Accessibility Guidelines) standards. A contrast ratio of at least 4.5:1 is recommended for normal text and 3:1 for large text. Additionally, avoid using this color for crucial UI elements without a clear visual indicator, as users with visual impairments may struggle to identify them. Providing alternative text and keyboard navigation support is also essential.

Shades

Digital Color Formats

RGB
1 51 179
RGB1 51 179
Red
Green
Blue
HSL
223.15deg 98.89% 35.29%
223.1598.8935.29HSL
Hue
Saturation
Lightness
HWB
223.15deg 0.39% 29.8%
223.150.3929.8HWB
Hue
Whiteness
Blackness
hex#0133B3
rgb1 51 179
hsl223.15deg 98.89% 35.29%
cmyk99.44% 71.51% 0% 29.8%
hwb223.15deg 0.39% 29.8%
xyz-d650.09 0.06 0.43
oklch0.3986 0.2057 263.36
oklab0.3986 -0.02 -0.2
CMYK
99.44% 71.51% 0% 29.8%
99.4471.51029.8CMYK
Cyan
Magenta
Yellow
Key
XYZ-d65
0.09 0.06 0.43
0.090.060.43XYZ
X
Y
Z
OKLCH
0.3986 0.2057 263.36
0.39860.2057263.36LCH
Lightness
Chroma
Hue
OKLAB
0.3986 -0.02 -0.2
0.3986-0.02-0.2LAB
Lightness
Green-Red
Blue-Yellow

Alternative colors

Applications

Complementary color

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