ANOVA & Group Comparisons

A two-sample t-test compares two groups. These tools compare three or more groups at once, without inflating your false-positive rate by running many pairwise t-tests instead. Every engine here reports cell sizes, group means and standard deviations, the omnibus test statistic, degrees of freedom, p-value, and an effect size together.

These tools calculate group sample sizes, the observed variance ratio, and residuals directly from your data, but a significant omnibus test does not by itself identify which specific groups differ, and whether your design is genuinely independent or repeated measures is left for you to specify correctly.