Repeated Measures ANOVA Calculator

Analyze within subject designs with precision using this repeated measures ANOVA tool Build a data table compute sums of squares F statistic p value and partial eta squared Validate assumptions explore residuals and export results for reports Get cell means subject means condition means effect size guidance and tips for interpreting outcomes across sessions

How to use
  1. Set the number of subjects and conditions, then click Build Table.
  2. Enter each subject’s score for every condition. Use Fill Example to see a demo dataset.
  3. Click Compute ANOVA to view the ANOVA table, effect size, and decision.

This tool runs a one-way within-subjects ANOVA: SSTotal = SSConditions + SSSubjects + SSError; F = MSConditions / MSError.

FAQs
It tests whether mean differences across related conditions or time points are greater than expected by chance while accounting for subject level variability.
Normally distributed residuals equal variances of differences between condition pairs sphericity and independence of observations within subjects design.
The error is the interaction of subjects with conditions computed as SSError = SSTotal − SSConditions − SSSubjects.
The p value comes from the F distribution with df1 = k − 1 and df2 = (k − 1)(n − 1) using an incomplete beta function implementation.
It is an effect size estimating the proportion of variance in scores attributable to the condition after removing subject and error variance.
This page does not include Mauchly’s test or epsilon corrections. For many designs with three or more levels consider external checks and apply corrections when sphericity is doubtful.
This calculator requires a complete data matrix. If values are missing impute them carefully or drop subjects before running the analysis.
If the main effect is significant follow up with planned contrasts or pairwise comparisons adjusted for multiple testing to locate specific differences between conditions.

Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.