Σ Analyzers
Math
Quartile & Outlier Analyzer
Find quartiles, IQR, outlier fences, and possible outliers from a numerical dataset.
Quartiles and the 1.5 × IQR rule
The analyzer sorts the dataset, finds the median and quartiles using a median-of-halves method, then flags values outside the common 1.5 × IQR fences.
How this resource works
IQR = Q3 − Q1. Lower fence = Q1 − 1.5 × IQR. Upper fence = Q3 + 1.5 × IQR. Values outside the fences are flagged as possible outliers.