The only SPC platform with Decimal 28+ digit precision, QI-compliant rules, automatic phase detection, and dynamic control limits — all in your browser.
28+
Digit Precision
17
Chart Types
27
Languages
More precise than QI Macros. More accessible than Minitab. Built for the modern web.
Python Decimal engine. No IEEE 754 rounding errors. Every digit matters.
P and U charts compute limits per point based on individual subgroup sizes.
Shift, Trend, Runs, Astronomical point detection with exact p-values.
Pettitt change-point analysis finds process shifts automatically.
Run, I-MR, X̄-R, X̄-S, P, NP, U, C — complete SPC coverage.
All 8 rules with statistical significance testing and p-values.
Instant results with interactive Plotly charts and export to Excel.
Works everywhere. Collaborate with your team. Never lose your data.
Coming soon — automatic interpretation and improvement suggestions.
Paste your data below and get instant SPC analysis — powered by PELT algorithm and QI rules.
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