The only SPC platform with Decimal 28+ digit precision, IHI-compliant rules, automatic phase detection, and dynamic control limits — all in your browser.
28+
Digit Precision
8
Chart Types
12
Statistical Rules
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.
Join quality professionals who trust FastQI for their SPC analysis.
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