Statistics & Probability
Statistics calculators for descriptive measures, probability distributions, regression, correlation, confidence intervals and sampling error, each stating the assumptions it makes.
T-Statistic Calculator
Calculate a one-sample t-statistic from a sample mean, population mean and st…
Cohen's d Calculator
Calculate Cohen's d, the standardised difference between two means.
Relative Risk Calculator
Calculate relative risk from a 2×2 table, with the absolute difference that u…
Odds Ratio Calculator
Calculate an odds ratio from a 2×2 table, the standard measure for case-contr…
Sensitivity and Specificity Calculator
Calculate sensitivity, specificity and predictive values from a diagnostic te…
Number Needed to Treat Calculator
Calculate number needed to treat from event rates in two groups, with the abs…
Chi-Square Statistic Calculator
Calculate a chi-square statistic from observed and expected counts.
Sample Proportion Calculator
Calculate a sample proportion with its standard error and 95% confidence inte…
Percentile Rank Calculator
Calculate percentile rank using the mid-point convention for tied scores.
Chebyshev's Theorem Calculator
Apply Chebyshev's inequality to find the minimum share of any dataset within …
Relative Frequency Calculator
Convert a raw count into relative frequency, percentage and odds.
Margin of Error Calculator
Calculate the margin of error on a survey proportion at any confidence level.
Poisson Distribution Calculator
Calculate Poisson probabilities for counts of events arriving at a known aver…
Coin Flip Probability Calculator
Calculate the probability of an exact number of heads in a run of coin flips.
Binomial Distribution Calculator
Calculate binomial probability for an exact number of successes, with the dis…
About the statistics & probability
Statistics calculators for descriptive measures, probability distributions, regression, correlation, confidence intervals and sampling error, each stating the assumptions it makes. There are 15 calculators in this category, and each one shows the formula it uses, works instantly as you type, and keeps your figures on your own device.
Cannot find what you need? Ask for it — requested calculators go to the front of the build queue.