Statistics calculators

Probability, sampling, and descriptive statistics made readable.

Means, medians, standard deviations, confidence intervals, and sample size planning — with formulas and worked examples for each tool.

Calculators

103

Topics: All Descriptive (29) Probability (35)

Statistics

F-Test Variance Ratio Calculator

Compute the F-statistic for comparing two sample variances (the larger over the smaller) and report the numerator and de...

basic

8,868 5.0 1 min

Statistics / Descriptive

Pearson Correlation from Sums Calculator

Computes the Pearson correlation coefficient r from aggregate statistics without raw data: r = [nΣXY − ΣXΣY] / √{[nΣX² −...

basic

7,547 4.1 1 min

Statistics

Sample Skewness of 5 Numbers Calculator

Compute the adjusted Fisher-Pearson sample skewness g₁ for a 5-number list. Positive values indicate a longer right tail...

basic

21,310 4.5 1 min

Statistics

ROC AUC (Trapezoid) from 5 Points Calculator

Compute the area under a ROC curve using the trapezoidal rule on 5 user-supplied (FPR, TPR) operating points (plus the i...

basic

5,696 4.7 1 min

Statistics / Probability

Binomial Distribution Exact Probability (PMF) Calculator

Calculates the exact binomial probability P(X = k) = C(n,k) · pᵏ · (1−p)^(n−k), the mean μ = n·p, and standard deviation...

basic

5,601 4.0 1 min

Statistics / Descriptive

Z-Score from Raw Score, Mean, and SD Calculator

Calculates the z-score: z = (X − μ) / σ, indicating how many standard deviations X is from the mean μ. Also computes the...

basic

22,445 4.7 1 min

Statistics

Sample Excess Kurtosis of 5 Numbers Calculator

Compute the adjusted excess kurtosis g₂ of a 5-number list (zero for a normal distribution; positive = heavier tails / m...

basic

22,133 4.0 1 min

Statistics / Probability

Catan Number Roll Probability Calculator

For Catan and other 2d6 games, compute the probability that at least one of your favoured numbers will come up over K ro...

basic

5,246 4.6 1 min

Statistics / Probability

Expected Value of 5 Outcomes Calculator

Compute the expected value of a discrete random variable defined by up to five (probability, payoff) pairs. Reports E[X]...

basic

17,215 4.9 1 min

Statistics / Descriptive

Confidence Interval for Mean (Known σ) Calculator

Constructs a confidence interval for a population mean using the z-distribution: CI = x̄ ± z* · (σ/√n). Common z* values...

basic

3,239 4.5 1 min

Statistics / Probability

Geometric Distribution PMF Calculator

Compute P(X = k), the probability that the first success in a Bernoulli sequence occurs on trial k, using the shifted ge...

basic

19,291 4.3 1 min

Statistics / Descriptive

Sample Variance and Standard Deviation from Summary Stats Calculator

Calculates sample variance s² = [Σx² − (Σx)²/n] / (n−1) and sample standard deviation s = √s² from the sum of squares, s...

basic

17,189 4.4 1 min

Statistics

Mean Absolute Error of 5 Pairs Calculator

Compute the mean absolute error (MAE) and root-mean-square error (RMSE) of up to five (actual, predicted) pairs — useful...

basic

10,273 4.6 1 min

Statistics / Probability

Binomial Coefficient (n choose k) Calculator

Compute the binomial coefficient "n choose k" using factorials. Useful for combinations, Pascal's triangle, and binomial...

basic

23,731 4.4 1 min

Statistics / Probability

Normal Distribution PDF Calculator

Compute the probability density function of a normal distribution N(μ, σ²) at a given value x, using f(x) = exp(−(x − μ)...

basic

19,289 4.9 1 min

Statistics / Probability

Exponential Distribution PDF Calculator

Compute the probability density function f(t) = λ · e^(−λt) and the survival function S(t) = e^(−λt) of an exponential d...

basic

19,613 4.8 1 min

Statistics / Probability

Chi-Square Test Statistic (4 categories)

Compute the χ² goodness-of-fit test statistic for up to four categories, given the observed counts and the expected coun...

basic

21,010 4.3 1 min

Statistics

Binomial Distribution PMF & CDF Calculator

Calculates the binomial probability mass function P(X = k) and cumulative distribution P(X ≤ k) from trials n, success p...

basic

10,447 4.8 1 min

Statistics

Poisson Distribution Event Rate Calculator

Calculates the Poisson PMF and CDF from event rate λ and number of events k for modelling rare events in a fixed time/sp...

basic

9,999 4.8 1 min

Statistics

Geometric Distribution First-Success Trial Calculator

Calculates the probability of achieving the first success on exactly the k-th trial in a geometric distribution, plus me...

basic

21,787 4.7 1 min

Statistics

F-Test Variance Ratio ANOVA Calculator

Calculates the F-statistic for comparing two sample variances (F-test for equality of variances) from sample standard de...

basic

10,233 4.8 1 min

Statistics

Two-Sample Independent t-Test Calculator

Calculates Welch's t-statistic and approximate degrees of freedom for comparing means of two independent samples.

basic

15,839 4.9 1 min

Statistics

Hypergeometric Distribution Urn Model Calculator

Calculates the hypergeometric probability of drawing exactly k successes from a finite population without replacement.

basic

13,504 4.2 1 min

Statistics

Chi-Squared Observed vs Expected Test Calculator

Calculates the chi-squared test statistic for a goodness-of-fit test from up to five categories with observed and expect...

basic

18,065 4.0 1 min

Showing 25 to 48 of 103 results

About this category

Means, medians, standard deviations, confidence intervals, and sample size planning — with formulas and worked examples for each tool.

Got a suggestion?

Missing a calculator in Statistics? We'd love to hear what to build next.

Request a calculator

Calcify

Browse categories

Statistics calculators

F-Test Variance Ratio Calculator

Pearson Correlation from Sums Calculator

Sample Skewness of 5 Numbers Calculator

ROC AUC (Trapezoid) from 5 Points Calculator

Binomial Distribution Exact Probability (PMF) Calculator

Z-Score from Raw Score, Mean, and SD Calculator

Sample Excess Kurtosis of 5 Numbers Calculator

Catan Number Roll Probability Calculator

Expected Value of 5 Outcomes Calculator

Confidence Interval for Mean (Known σ) Calculator

Geometric Distribution PMF Calculator

Sample Variance and Standard Deviation from Summary Stats Calculator

Mean Absolute Error of 5 Pairs Calculator

Binomial Coefficient (n choose k) Calculator

Normal Distribution PDF Calculator

Exponential Distribution PDF Calculator

Chi-Square Test Statistic (4 categories)

Binomial Distribution PMF & CDF Calculator

Poisson Distribution Event Rate Calculator

Geometric Distribution First-Success Trial Calculator

F-Test Variance Ratio ANOVA Calculator

Two-Sample Independent t-Test Calculator

Hypergeometric Distribution Urn Model Calculator

Chi-Squared Observed vs Expected Test Calculator