Online Number Outlier Detector

Find values outside IQR fences in at least four finite numbers; preserve input order and repeated outliers. Processing takes place locally in your browser.

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Online Number Outlier Detector

Quartiles use sorted[floor((n−1)p)] at p=0.25 and 0.75, without interpolation. IQR=Q3−Q1; the fences are Q1−1.5×IQR and Q3+1.5×IQR. Only values strictly outside are selected; values on a fence are excluded. Order and duplicates are preserved. The result shows lower bound, upper bound and outliers, without a separate Q1/Q3/IQR display.

Limits: 100000 UTF-16 code units and 10000 values. Non-finite fences are rejected. JavaScript Number and the display can round, especially near a fence; output uses up to 15 significant digits without grouping and separates outliers with semicolons. There is no download or automatic deletion. This exploratory rule can differ from interpolating software and does not prove error, fraud or clinical abnormality. Keep source data and use validated analysis for important decisions.

Processing takes place locally in your browser.