Calculators

Statistics calculators

Use standalone tools for focused calculations, or try embedded examples inline.

• Tool Average Calculator Calculate the average of a data set using the arithmetic mean formula, entering any list of numbers to get an instant, step-by-step result.
• Tool Binomial Distribution Calculator Calculate exact and cumulative binomial probabilities for a chosen number of trials, success probability, and outcome count.
• Tool Chi Square Calculator Calculate a chi-square goodness-of-fit statistic and its upper-tail p-value from the observed and expected counts that you enter.
• Tool Combination Calculator Calculate combinations (nCr) or permutations (nPr) from n and r, useful for probability problems and counting arrangements.
• Tool Confidence Interval Calculator Calculate a z-based confidence interval for a population mean, showing the margin of error and the lower and upper bounds.
• Tool Correlation Coefficient Calculator Calculate Pearson's correlation coefficient for paired x and y values, showing r-squared and the strength of the relationship.
• Tool Factorial Calculator Calculate n! (n factorial) for any non-negative integer, showing the multiplication steps used to reach the final result.
• Tool Frequency Distribution Table Generator Build a sorted frequency table from raw data, showing relative and cumulative frequency for each distinct value automatically.
• Tool Linear Regression Calculator Fit a least-squares regression line for paired x and y values, returning the slope, intercept, and correlation coefficient.
• Tool Mean Absolute Deviation Calculator Calculate the mean absolute deviation of a data set, measuring the average distance of each value from the mean without squaring.
• Tool Mean Calculator Calculate the mean (average) of any set of numbers, see the sum and count used, and get the result instantly with no sign-up required.
• Tool Normal Distribution Calculator Calculate normal distribution probabilities for one bound or an interval, using the mean and standard deviation that you enter.
• Tool P Value Calculator Calculate left-tail, right-tail, or two-sided p-values from a z or Student-t test statistic, with support for degrees of freedom.
• Tool Percentile Calculator Calculate a percentile value and the quartiles (Q1, Q2, Q3) for any data set, showing the interquartile range in the same result.
• Tool Probability Calculator Calculate simple probability from the number of favorable and total outcomes, and see the complement probability at the same time.
• Tool Proportion Calculator Solve the missing fourth term in a proportion of the form a/b = c/d, useful for scaling recipes, rates, and ratio problems.
• Tool Range Calculator Find the range of a data set along with its minimum and maximum values, calculated instantly from any list of numbers you enter.
• Tool Sample Size Calculator Estimate the sample size needed to estimate a population proportion at a chosen confidence level and margin of error.
• Tool Standard Deviation Calculator Calculate sample or population standard deviation for any data set and see how far values typically spread from the mean, step by step.
• Tool T Table Calculator Look up critical t values by confidence level, degrees of freedom, and one- or two-tailed test, replacing a printed t table.
• Tool T-Test Calculator Run a one-sample t-test from a sample mean, hypothesized mean, sample standard deviation, and sample size, with the p-value shown.
• Tool Variance Calculator Calculate both sample and population variance for a data set, showing the sum of squared deviations used behind each formula.
• Tool Weighted Average Calculator Calculate a weighted average from matching lists of values and weights, useful for course grades, investment portfolios, and survey scoring.
• Tool Z Table Calculator Calculate the standard normal left-tail probability for any z-score, along with the right-tail and between-zero-and-z values.
• Tool Z-Score Calculator Calculate a z-score from a raw value, mean, and standard deviation to see how many standard deviations it falls from average.