Statistics & Probability Calculators
Mean, deviation, probability and intervals.
Summarize data with mean, median and standard deviation, compute probability and combinatorics, and build confidence intervals and sample sizes.
All 11 statistics & probability calculators
Combinatorics (factorial) CalculatorCompute n!, permutations with repetition (nʳ) and combinations with repetition.Confidence Interval CalculatorEstimate the confidence interval for a mean from the sample mean, standard deviation and size.Mean, Median, Mode, Range CalculatorFind the mean, median, mode(s) and range of a list of numbers at once, so you can see how the average shifts when outliers are present.P-value CalculatorConvert a z test statistic into a p-value for a left, right or two-tailed test.Permutation and Combination CalculatorCalculate permutations (nPr) and combinations (nCr) for choosing r items from n.Probability CalculatorCombine the probabilities of two independent events to find P(A and B), P(A or B) and P(not A).Ratio CalculatorSolve a proportion a:b = c:d for any missing term and simplify a ratio.Sample Size CalculatorFind how many responses you need for a survey at a given confidence level and margin of error.Standard Deviation CalculatorCalculate the mean, variance and standard deviation of a dataset (population or sample).Statistics CalculatorGet count, sum, mean, range, variance, standard deviation and quartiles from a list of numbers.Z-score CalculatorFind how many standard deviations a value is from the mean, plus its percentile.