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METHODS & LIMITS

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Our reference values are transparent, reproducible, and deliberately separated from device-specific production claims.

Source color space

HEX and RGB values are interpreted as standard sRGB channel values from 0 to 255. HSL uses the conventional cylindrical transformation of sRGB values.

Pantone reference matching

The Pantone chart contains 3,217 coated and uncoated digital simulations from the MIT-licensed pantone-table dataset. Input colors are converted to CIE L*a*b* using a D65 sRGB reference, then ranked using simple ΔE76 distance. RAL and NCS cross-system results use the same approximate perceptual comparison.

This is not official Pantone data. A short digital color distance does not identify an ink formula or guarantee a physical match. Use current Pantone publications, licensed tools, and physical proofs for production.

Generic CMYK conversion

For a normalized RGB triplet, the black channel is calculated as one minus the largest RGB channel. Cyan, magenta, and yellow are then calculated relative to the remaining non-black component. Results are rounded to whole percentages.

This is not an ICC conversion. The formula has no knowledge of a printing condition, paper color, dot gain, black generation, or total area coverage. It is a convenient reference—not a separation recipe for production.

Contrast ratios

The contrast checker linearizes sRGB channels, calculates WCAG relative luminance, then compares the lighter and darker values using the standard luminance ratio formula. Threshold labels follow WCAG AA and AAA ratios for normal and large text.

Versioning

Methodology last reviewed August 12, 2026. Material changes to calculations or source datasets will be recorded here before deployment.

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