Raster CMYK Separation & TAC Preview
The browser converts RGB pixels with a simple mathematical CMYK model to create diagnostic channel previews and a user-set TAC heatmap. It is explicitly not ICC color conversion.
See channel structure and high-coverage regions
This is deliberately a mathematical RGB→CMYK diagnostic, not an ICC conversion. It is useful for seeing where channel density exists before opening the original file in a profile-aware production workflow.
Color numbers only become meaningful inside an output condition
PDF color-space and output-intent signals help diagnose a job, but browser-side token inspection does not replace a color-managed separation preview or printer-specific preflight.
Color-space, output-intent, spot/separation or overprint tokens that can be read from the file.
Which profile, TAC limit, black build or conversion policy is correct for this output condition.
Use the printer/prepress profile, proofing workflow and professional output preview where the job is color-critical.
What the result is useful for
The preview makes four-channel structure and high-coverage regions visible before a professional profile/output preview is run.
How the calculation works
For each RGB pixel, K = 1 − max(R,G,B); C/M/Y are normalized from the remaining channels. TAC = C+M+Y+K.
What this calculator cannot know
RGB-to-CMYK conversion is profile-dependent. This mathematical preview cannot predict press separations, black generation, gamut mapping or actual ink limits.