Statistics Calculators86 calculators
Understanding statistics does not have to be intimidating. These calculators are designed to help with everything from probability questions to analyzing data sets for class projects or research. Tackle confidence intervals, work out regression analysis, and check probabilities with clear, practical tools. Each calculator focuses on straightforward results and clear explanations, so you can focus on the data itself and make sense of the numbers in front of you.
Descriptive
Box Plot Analysis Calculator
Calculate the five-number summary, IQR, fences, and detect outliers from up to 10 data values for box-and-whisker plot construction.
Coefficient of Variation Calculator
Calculate the coefficient of variation (CV) to compare relative variability between data sets with different units or means.
Descriptive Statistics Calculator
Calculate mean, median, mode, range, variance, standard deviation, and more from up to 10 data values.
Five-Number Summary Calculator
Calculate the five-number summary (min, Q1, median, Q3, max) from a normal distribution using mean and standard deviation.
Frequency Distribution Calculator
Group data into frequency classes. Calculate class width, boundaries, and expected frequencies for histogram construction.
Interquartile Range (IQR) Calculator
Calculate the interquartile range (IQR), outlier fences, and spread measures from Q1 and Q3 values or from mean and standard deviation.
Least to Greatest Calculator
Sort a list of numbers from smallest to largest. Also shows the range, minimum, maximum, and count.
Mean Absolute Deviation Calculator
Calculate the Mean Absolute Deviation (MAD) from up to 10 data values. Shows the average distance from the mean.
Mean, Median & Mode Calculator
Calculate the mean (average), median (middle value), and mode (most frequent value) of any data set.
Median Calculator
Find the median of a dataset with up to 10 values. Also shows mean, count, min, max, range, and sorted order.
Mode Calculator
Find the mode (most frequent value) of a dataset, determine if it is unimodal, bimodal, or multimodal, and see the frequency of each value.
Moving Average Calculator
Calculate simple moving average (SMA) and exponential moving average (EMA) from a time series to identify trends and smooth out short-term fluctuations.
Outlier Calculator
Detect outliers in a data set using the IQR method and z-score method. Enter up to 10 values to identify which points are outliers.
Percentile Calculator
Calculate what percentile a score falls in, or find the score at a given percentile using a normal distribution.
Pie Chart Percentage Calculator
Calculate the percentages and degree angles for a pie chart from category values. Determine each slice's share of the total.
Quartile Calculator
Calculate Q1, Q2 (median), and Q3 quartiles from a normal distribution using mean and standard deviation.
Relative Standard Deviation Calculator
Calculate the relative standard deviation (%RSD) from a data set. RSD equals (standard deviation / mean) × 100.
Sample Variance Calculator
Calculate sample variance and population variance from a comma-separated data set. Also shows standard deviation and mean.
Skewness & Kurtosis Calculator
Calculate skewness and kurtosis from summary statistics to assess the shape of a distribution's symmetry and tail heaviness.
Standard Deviation Calculator
Calculate the standard deviation, variance, and other dispersion measures for any data set. Supports both population and sample calculations.
Distributions
Binomial Distribution Calculator
Calculate binomial probabilities P(X = k), P(X ≤ k), and P(X ≥ k) for a given number of trials, successes, and probability of success.
Critical Value Calculator
Look up critical values for z, t, chi-square, and F distributions at common significance levels.
Exponential Distribution Calculator
Calculate probabilities for the exponential distribution, modeling time between events. Find P(X < x), P(X > x), and the PDF value.
F-Distribution / F-Test Calculator
Calculate the F-statistic and approximate p-value for comparing two sample variances using the F-test.
Hypergeometric Distribution Calculator
Calculate hypergeometric probabilities for sampling without replacement. Find the probability of drawing exactly k successes.
Inverse Normal Distribution Calculator
Find the z-score or x-value for a given cumulative probability. Calculates the inverse CDF (quantile function) of the normal distribution.
Negative Binomial Distribution Calculator
Calculate the probability of needing exactly k trials to achieve r successes, with expected trials and variance.
Normal Distribution Calculator
Calculate probabilities and z-scores for the normal distribution. Find P(X < x), P(X > x), and P(a < X < b) given mean and standard deviation.
Poisson Distribution Calculator
Calculate Poisson probabilities P(X = k), P(X ≤ k), and P(X ≥ k) for a given average rate of occurrence (lambda).
Uniform Distribution Calculator
Calculate probabilities and statistics for the continuous uniform distribution on the interval [a, b].
Z-Score Calculator
Calculate the z-score (standard score) using z = (x - μ) / σ. Find how many standard deviations a value is from the mean.
Inference & Regression
95% Confidence Interval Calculator
Calculate a 95% confidence interval for a population mean from sample data. Uses z-score (1.96) for large samples or t-score for small samples.
A/B Test Calculator
Determine if your A/B test results are statistically significant using a two-proportion z-test.
Chi-Square Test Calculator
Calculate the chi-square test statistic and approximate p-value for a goodness-of-fit or independence test with observed and expected frequencies.
Cohen's D Calculator
Calculate Cohen's d effect size from two group means and standard deviations. Includes pooled SD, Hedges' g correction, and effect size interpretation.
Cohen's Kappa Calculator
Calculate Cohen's kappa coefficient for inter-rater agreement from a 2x2 agreement matrix. Shows observed agreement, expected agreement, and agreement strength.
Confidence Interval Calculator
Calculate confidence intervals for a population mean using sample statistics. Supports 90%, 95%, and 99% confidence levels.
Correlation Coefficient Calculator
Calculate the Pearson correlation coefficient (r) and R-squared from summary statistics to measure the linear relationship between two variables.
Covariance Calculator
Calculate the covariance between two variables to measure how they change together, along with the correlation coefficient and direction of association.
Cronbach's Alpha Calculator
Calculate Cronbach's alpha for internal consistency reliability using either item variances or average inter-item correlation.
Fisher's Exact Test Calculator
Perform Fisher's exact test on a 2x2 contingency table to test for association between two categorical variables.
Friedman Test Calculator
Perform the Friedman test for non-parametric repeated measures. Enter data for n subjects across k conditions to get the Q statistic, degrees of freedom, and p-value.
Hypothesis Test Setup Calculator
Set up and evaluate a hypothesis test. Determine the test statistic, critical value, and conclusion for one-sample z-tests and t-tests.
ICC Calculator
Calculate the intraclass correlation coefficient (ICC) for inter-rater reliability. Enter ratings from multiple raters on multiple subjects.
Kruskal-Wallis Test Calculator
Perform the Kruskal-Wallis H test (non-parametric one-way ANOVA) for 2-4 groups. Get the H statistic, degrees of freedom, and approximate p-value.
Linear Regression Calculator
Calculate the linear regression equation (y = mx + b), R-squared, and predicted value from summary statistics.
Linear Regression Equation Calculator
Compute the linear regression equation (y = b0 + b1*x) from paired data, including slope, intercept, R-squared, and predictions for new x values.
Log-Rank Test Calculator
Compare two survival curves using the log-rank (Mantel-Cox) test. Enter event times and censoring for two groups to get the test statistic and p-value.
Mann-Whitney U Test Calculator
Perform the Mann-Whitney U test (Wilcoxon rank-sum test) to compare two independent samples without assuming normal distribution.
McNemar's Test Calculator
Perform McNemar's test for paired nominal data. Enter a 2x2 table of matched pairs to get the chi-square statistic, p-value, and odds ratio.
One-Way ANOVA Calculator
Perform a one-way analysis of variance (ANOVA) using group summary statistics to test if group means differ significantly.
Probability
Bayes' Theorem Calculator
Calculate posterior probability using Bayes' theorem. Given prior probability, sensitivity, and false positive rate, find the updated probability.
Coin Flip Probability Calculator
Calculate the probability of getting a specific number of heads (or tails) in a series of coin flips, including biased coins.
Combination & Permutation Calculator
Calculate nCr (combinations) and nPr (permutations) for any values of n and r.
Dice Average Calculator
Calculate the expected average, variance, and standard deviation for dice rolls. Supports standard polyhedral dice (d4 through d20).
Dice Probability Calculator
Calculate the probability of rolling a specific sum with multiple dice. Supports 4, 6, 8, 10, 12, and 20-sided dice.
Effect Size Calculator
Calculate Cohen's d effect size to measure the practical significance of the difference between two group means.
Expected Value Calculator
Calculate the expected value (mean) of a discrete random variable from up to 6 outcome-probability pairs.
Geometric Probability Calculator
Calculate geometric distribution probabilities. Find the probability of first success on trial k, cumulative probabilities, and expected value.
Implied Probability Calculator
Convert betting odds (American, decimal, fractional) to implied probability. Compare the true probability to find value bets.
Lottery Odds Calculator
Calculate the odds of winning a lottery jackpot based on the number pool and pick count, with optional bonus ball.
Margin of Error Calculator
Calculate the margin of error for a survey or poll based on sample size, confidence level, and proportion.
Odds Ratio Calculator
Calculate the odds ratio from a 2x2 contingency table to measure the association between exposure and outcome.
Poker Odds Calculator
Calculate Texas Hold'em hand odds from your number of outs. Get turn odds, river odds, and combined odds using the Rule of 2 and 4.
Probability Calculator
Calculate the probability of an event from favorable and total outcomes, including complement probability.
Relative Risk Calculator
Calculate the relative risk (risk ratio) from a 2x2 contingency table to compare event rates between exposed and unexposed groups.
Sample Size Calculator
Determine the minimum sample size needed for a survey or study at your desired confidence level and margin of error.
Sampling Distribution Calculator
Calculate the sampling distribution of the mean, including the standard error, confidence interval, and the probability of the sample mean falling within a given range.
Sensitivity & Specificity Calculator
Calculate sensitivity, specificity, PPV, NPV, accuracy, prevalence, F1 score, and likelihood ratios from a 2x2 contingency table.
Simpson's Diversity Index Calculator
Calculate Simpson's diversity index (D), Simpson's index of diversity (1-D), and Simpson's reciprocal index (1/D) from species counts.
Statistical Power Analysis Calculator
Calculate the required sample size for a given effect size, significance level, and desired statistical power.