Statistics Calculators Calculators
Standard deviation, median, z-scores, probability and sample size.
Wahrscheinlichkeitsrechner
Work out how two events relate: independence, mutual exclusivity, conditional probability and Bayes’ theorem, with all four regions of the sample space.
Variance Calculator
Variance calculator for a list of numbers: sample or population variance, standard deviation, coefficient of variation and the full deviation table.
Standard Error Calculator
Compute the standard error of the mean (SEM = s/√n), the standard error of a proportion (√(p(1−p)/n)), or the standard error of the difference between two independent means (√(s₁²/n₁ + s₂²/n₂)).
Uncertainty Calculator
Measurement uncertainty calculator following the GUM: Type A from repeated readings, Type B from tolerances, combined in quadrature, and expanded to a quoted result at any coverage probability.
Upper Fence Calculator
Upper fence calculator for outlier screening: how many values a Tukey, median deviation or standard deviation fence flags, how far past it the worst reading lies, and what trimming it does to the mean.
Upper Control Limit Calculator
Upper control limit calculator for a Shewhart X-bar chart: centre line, UCL and LCL from subgroup means and ranges, raw observations or a known process standard deviation.
Upper and Lower Fence Calculator
Upper and lower fence calculator: Tukey inner and outer fences, median absolute deviation fences and standard deviation fences, with every value labelled against them.
Venn Diagram Calculator
Solve a three-set Venn diagram: fill in the seven regions and get every set size, overlap and union, or work backwards from set sizes and intersections.
Uniform Distribution Calculator
Uniform distribution calculator for cumulative probabilities, densities, quantiles, window probabilities and generated samples across any lower and upper bound.
Two Dice Probability Calculator
Two dice probability calculator for the chance of a total, both tails of a threshold, one specific pair, loaded dice, and a simulation against the exact distribution.
Third Quartile Calculator
Third quartile calculator for the 75th percentile under the inclusive, exclusive and Tukey hinge conventions, plus the top quarter, a top-quartile score threshold and grouped data.
Sum of Squares Calculator
Sum of squares calculator for the deviations from the mean, sums of squares about any reference value, the computational shortcut, and the one-way ANOVA split.
Two Envelopes Paradox Calculator
Work out whether you should switch envelopes, see the posterior chance that you hold the larger amount, and find where the two-envelopes paradox stops making sense.
Weibull Distribution Calculator
Weibull distribution calculator for probabilities, densities, hazard rates, quantiles and generated samples, with the moments of the fitted shape and scale.
Youden Index Calculator
Calculate Youden’s index (sensitivity + specificity − 1) from a 2×2 table of true and false positives and negatives, with balanced accuracy and likelihood ratios.
Wilcoxon Rank-Sum Test Calculator
Run the Wilcoxon rank-sum test (Mann–Whitney U) on two independent samples, with an exact p-value when possible, tie correction, continuity correction and effect size.
Mann-Whitney U Test Calculator
Work out the Mann-Whitney U statistic from two independent samples, see the pairwise comparisons behind it, and read an exact or normal-approximation p-value with the critical U for your significance level.
Z-score Calculator
Convert any value into a z-score, see how far it sits from the mean in standard deviations, and read its percentile rank in a normal distribution.
Z-test Calculator
Test a sample mean against a known population mean when the population standard deviation is known, with p-value, critical value and confidence interval.
t-statistic Calculator
Compute the t statistic for a one-sample, two-independent-sample or paired design, with Welch degrees of freedom, Cohen’s d and Hedges’ g.
t-test Calculator
Run a one-sample, two-independent-sample or paired Student’s t test with the p-value, confidence interval, decision and Cohen’s d.
p-value Calculator
Turn a test statistic into a p-value against the normal, t, chi-square or F distribution — or from a Pearson correlation — and see the decision.
About Statistics Calculators Calculators
This collection features 22 specialized calculators, formulas, and tools.
Statistics calculators for descriptive and inferential work: mean, median, mode, standard deviation, z-scores, normal distribution probabilities, confidence intervals and how many samples you need for a survey.