Nonparametric Test Calculators
Rank-based tests for ordinal data such as Likert ratings, or for continuous data that is clearly not normal. Each test is the nonparametric counterpart of a t-test or ANOVA.
Mann-Whitney U Test Calculator
Nonparametric comparison of two independent groups, with exact p-values for small samples.
Replaces SPSS · PrismWilcoxon Signed-Rank Test Calculator
Nonparametric test for two related measurements, the alternative to the paired t-test.
Replaces SPSS · PrismKruskal-Wallis H Test Calculator
Nonparametric comparison of three or more groups, with Dunn’s post-hoc tests.
Replaces SPSS · PrismFriedman Test Calculator
Nonparametric test for three or more related measurements, with Kendall’s W.
Replaces SPSS · PrismMann-Whitney U Test Calculator
Use it instead of the independent t-test for ordinal outcomes such as Likert ratings, or when the outcome is clearly non-normal with small groups.
Wilcoxon Signed-Rank Test Calculator
Use it for pre-post or matched data when differences are skewed or the outcome is ordinal.
Kruskal-Wallis H Test Calculator
Use it instead of one-way ANOVA for ordinal outcomes or when normality is badly violated with small groups.
Friedman Test Calculator
Use it for three or more related measurements of an ordinal outcome, or when repeated measures ANOVA assumptions fail.
Other categories
Data cleaning and preparation · Describe and explore · Compare means · Correlation and regression · Bayesian statistics · Categorical data · Reliability and agreement · Multivariate analysis · Structural equation modeling · Econometrics and time series · Panel data and causal inference · Marketing and decision research · Survival, clinical and meta-analysis · Study planning and calculators · PLS-SEM