Free Statistics Calculators for Researchers

Enter a test statistic and its degrees of freedom to get the exact p value for a z, t, chi-square (χ²) or F test, one- or two-tailed. Everything is computed in your browser, and you get an APA 7 sentence ready to copy.

Run a chi-square test of independence on any r×c contingency table, or a goodness-of-fit test against expected proportions. You get expected counts, χ², df, the p value, Cramér's V and an APA 7 sentence, all computed in your browser.

Compare means with a one-sample, paired or independent-samples t test (Student's or Welch's), using raw data or just means, SDs and sample sizes. You get t, df, p, the mean difference with a 95% confidence interval, Cohen's d and an APA 7 sentence.

Convert a raw score into a z score and percentile, turn a z score into tail probabilities, or standardise a whole column of data at once. Everything runs in your browser, with an APA-style sentence ready to copy.

Paste two columns of numbers to get Pearson's r with its p-value and 95% confidence interval, Spearman's rho, a scatter plot, and a ready-to-copy APA 7 sentence. Everything is computed in your browser, so your data is never uploaded.

Paste an X and a Y column to fit a simple linear regression. You get the equation, slope and intercept with standard errors, t and p values, R², adjusted R², the F test, residual standard error, a scatter plot with the fitted line, and an APA 7 sentence — all computed in your browser.

Compare the means of three or more independent groups. Paste raw scores or enter each group's n, mean and SD to get the ANOVA table, F, p-value and η², Welch's ANOVA for unequal variances, Tukey HSD pairwise comparisons, and an APA 7 sentence — computed entirely in your browser.

Enter the four counts of a 2×2 table to get the exact two-sided and one-sided p-values, the odds ratio with its 95% confidence interval, and a ready-to-copy APA 7 sentence. Built for small samples where the chi-square test is unreliable, and computed entirely in your browser.

Paste the raw values for two independent groups and get the Mann-Whitney U statistic, a z score with tie correction, an exact p-value for small samples without ties, the rank-biserial correlation, and a ready-to-edit APA 7 sentence.

Enter the four cell counts of a 2×2 table to get the odds ratio with a 95% confidence interval, the relative risk with its interval, an automatic Haldane correction when a cell is zero, and a ready-to-edit APA 7 sentence.

Compute Cohen's d and Hedges' g from two group means, standard deviations, and sample sizes, or from an independent-samples t statistic, then convert to r and η² with interpretation benchmarks and an APA 7 sentence you can edit.

Paste questionnaire item responses (rows = respondents, columns = items) to get Cronbach's alpha, standardized alpha, corrected item-total correlations, and alpha if each item is deleted, plus an APA 7 sentence for your methods section.

Fill in the numbers from your search and screening, and this tool draws a PRISMA 2020 flow diagram you can download as SVG or PNG for your systematic review. It runs entirely in your browser, so your counts are not uploaded.