Can your process actually hold the tolerances? Cp and Cpk turn that question into numbers — and reveal how fast defects climb when it drifts off-center.
Process Capability (Cp / Cpk)Live
how good is the process?
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Cp compares the spec width to the process spread — can the process fit inside the tolerances at all? Cpk also accounts for how well-centered it is. A Cpk of 1.33 is the usual bar for capable; 2.0 is Six Sigma quality with just 3.4 defects per million. Widen the spread or push the mean off-center and defects climb fast.
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How it works
Cp compares the specification width to the process spread, and Cpk also accounts for centering. A Cpk of 1.33 is the common bar for a capable process; 2.0 is Six Sigma, allowing only 3.4 defects per million. Widening the spread or shifting the mean toward a spec limit rapidly increases the defect rate — the heart of statistical quality control.
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Is this process capability Cp Cpk tool really free?▾
Yes. Process Capability (Cp / Cpk) runs entirely in your browser using your device's own compute, so local use is free forever. You only pay Compute Tokens if you scale a job to the cloud.
Do I need to install anything?▾
No. Everything runs client-side in a modern browser — no downloads, no license, no account required to start.
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How accurate are the results?▾
The solver uses established numerical methods, but results are for research and educational purposes and should be validated against experiment or professional review before you rely on them.