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.
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.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.