International Klein Blue

#0033B4

About International Klein Blue

International Klein Blue, often abbreviated as IKB, is a deep blue hue first mixed by the French artist Yves Klein. IKB's visual impact comes from its heavy reliance on ultramarine pigment and is a registered trademark. The color was developed as part of Klein's exploration into the limitless possibilities of color and its ability to evoke emotion. Klein sought to capture the purest expression of blue, aiming for a color that would embody the infinite and immaterial aspects of existence. He used the color in many of his paintings and sculptures, seeking a monochrome expression of art and is considered to be one of the most impactful colors.

The hex color #0033b4, also known as International Klein Blue, presents some accessibility challenges, particularly concerning color contrast. When using this color for text or interactive elements, it's crucial to ensure sufficient contrast against the background. According to WCAG guidelines, a contrast ratio of at least 4.5:1 is required for normal text and 3:1 for large text. Given the darkness of #0033b4, it's advisable to pair it with very light colors like white or very pale yellows to meet these standards. Tools like online contrast checkers can help to verify compliance. Also, providing alternative cues like underlines or icons for links can improve accessibility for users with color vision deficiencies. If sufficient contrast cannot be achieved, it might be more accessible to use a lighter tint or shade of this blue, or choose an entirely different color with better contrast.

Shades

Digital Color Formats

RGB
0 51 180
RGB0 51 180
Red
Green
Blue
HSL
223 100% 35.29%
22310035.29HSL
Hue
Saturation
Lightness
HWB
223 0% 29.41%
223029.41HWB
Hue
Whiteness
Blackness
hex#0033B4
rgb0 51 180
hsl223 100% 35.29%
cmyk100% 71.67% 0% 29.41%
hwb223 0% 29.41%
xyz9.42 5.66 43.78
CMYK
100% 71.67% 0% 29.41%
10071.67029.41CMYK
Cyan
Magenta
Yellow
Key
XYZ
9.42 5.66 43.78
9.425.6643.78XYZ
X
Y
Z

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