Repeated Measures ANOVA Calculator

About this calculator

A repeated-measures ANOVA tests whether the mean of a variable differs across conditions when the same subjects are measured under each condition, rather than comparing independent groups. Because each participant serves as their own control, it strips out between-person variability and can detect smaller effects than a standard between-subjects ANOVA with the same sample size.

This calculator computes the F statistic directly from your sums of squares and degrees of freedom: F = (SS_conditions/df_conditions) / (SS_error/df_error). It’s the standard test in psychology and behavioral research for before/after or multi-session designs, in medical studies tracking the same patients across treatment time points, and in sports science comparing an athlete’s performance across repeated trials or conditions.