General statistics reference and utility calculators. Browse our free general tools below — all calculators are instant, accurate, and require no sign-up.
Absolute Uncertainty Calculator — Calculate absolute, relative, and expanded uncertainty for measurements and propagate errors through addition, subtraction, multiplication, division, and powers.
Benford's Law Calculator — Test whether a dataset follows Benford's Law using chi-squared, K-S, and MAD statistics. Visualize leading digit distribution against expected frequencies.
Bertrand Box Paradox Calculator — Explore the Bertrand box paradox with interactive probability calculations, visual box displays, coin-level analysis, and Monte Carlo simulation.
Bertrand Paradox Calculator — Explore Bertrand's paradox of random chords with three methods, inscribed polygon comparison, probability visualization, and Monte Carlo simulation.
Chebyshev's Theorem Calculator — Apply Chebyshev's inequality to find the minimum proportion of data within k standard deviations of the mean, with normal distribution comparison.
Boy or Girl Paradox Calculator — Explore the boy-or-girl paradox with conditional probability for multiple scenarios, distribution tables, and Monte Carlo simulation verification.
Class Width Calculator — Calculate class width for frequency distributions using Sturges', Scott's, Freedman-Diaconis, and Rice rules. Generate class intervals automatically.
Cohen's d Calculator — Calculate Cohen's d, Hedges' g, and Glass's Δ effect sizes with CLES, overlap metrics, confidence intervals, and benchmark interpretation tables.
Confusion Matrix Calculator — Compute accuracy, precision, recall, F1, MCC, kappa, and 15+ classification metrics from TP/FP/FN/TN values with visual matrix and performance bars.
Continuity Correction Calculator — Apply Yates continuity correction for binomial-to-normal and Poisson-to-normal approximations with exact comparison, z-scores, and CDF tables.
Decile Calculator — Calculate deciles (D1-D9) from any dataset with three interpolation methods, decile range analysis, distribution bars, and color-coded sorted data display.
Critical Value Calculator — Find critical values for Z, t, chi-square, and F distributions by significance level and degrees of freedom with reference tables and rejection region visualization.
Decimal Odds Calculator — Convert between decimal, fractional, and American odds formats with implied probability, payout tables, stake analysis, and a complete conversion reference chart.
Degrees of Freedom Calculator — Calculate degrees of freedom for t-tests, ANOVA, chi-square, regression, and Welch's test with step-by-step formulas and a comprehensive reference table.
Dispersion Calculator — Calculate range, variance, standard deviation, IQR, MAD, CV, skewness, and kurtosis from any dataset with deviation tables, visual spread plot, and outlier detection.
Dot Plot Calculator — Generate interactive dot plots from data with frequency distribution tables, cumulative frequencies, summary statistics, and sortable output options.
Error Propagation Calculator — Propagate measurement uncertainties through addition, multiplication, powers, logarithms, and exponentials with error budget analysis and step-by-step derivations.
Empirical Rule Calculator (68-95-99.7) — Apply the 68-95-99.7 rule to normal distributions with bell curve visualization, section probabilities, z-score lookup, and Chebyshev comparison table.
F-Statistic Calculator — Calculate the F-statistic with p-value, critical value, ANOVA summary table, effect sizes (eta-squared, omega-squared), and rejection region visualization.
False Positive Rate Calculator — Calculate false positive rate, PPV, NPV, and 11 diagnostic metrics from prevalence, sensitivity, and specificity with confusion matrix and PPV-prevalence curve.
False Positive Paradox Calculator — Demonstrate the false positive paradox (base rate fallacy) with visual breakdowns, PPV-prevalence curves, retest analysis, and strategies for resolving the paradox.
Five-Star Rating Calculator — Analyze star ratings with simple average, Bayesian average, Wilson confidence, distribution visualization, polarity detection, and entropy-based consensus metrics.
Geometric Distribution Calculator — Calculate geometric distribution probabilities with PMF, CDF, waiting time tables, distribution visualization, and summary statistics for trials until first success.
Fractional Odds Calculator — Convert between fractional, decimal, American odds and implied probability with payout tables, profit calculations, and a comprehensive odds reference chart.
Greatest to Least Calculator — Sort numbers from greatest to least with visual bar chart, ranked data table showing percentiles, gaps, deviations, and a five-number summary with IQR.
Index of Qualitative Variation (IQV) Calculator — Calculate IQV, Blau's index, Shannon entropy, and Gini coefficient for categorical data with distribution visualization and diversity measure comparisons.
Least to Greatest Calculator — Sort numbers from least to greatest with number line visualization, ranked data table with percentiles, gap analysis, outlier detection, and five-number summary.
Least to Greatest Decimals Calculator — Sort decimal numbers from least to greatest with precision analysis, fraction approximation, number line visualization, and gap analysis for scientific data.
Moneyline Odds Calculator — Convert moneyline/American odds to decimal, fractional, and implied probability with payout tables, parlay builder, vig analysis, and common odds reference chart.
Lower Fence Calculator — Calculate lower and upper fences for outlier detection using IQR method with box plot visualization, outlier classification, and clean-data impact analysis.
Normal Approximation Calculator — Use the normal approximation to the binomial distribution. Calculate probabilities, z-scores, and check validity conditions with continuity correction.
Odds Calculator — Convert between probability, odds for, odds against, decimal, fractional, and American odds. Includes expected value tables and comparisons.
Ordering Decimals Calculator — Sort decimal numbers in ascending or descending order. Aligns decimal places, shows fraction approximations, gap analysis, and number line visualization.
Order from Least to Greatest Calculator — Sort numbers from least to greatest or greatest to least. Shows sorting steps, rank table, percentiles, number line, and position changes.
P-Hat Calculator — Calculate the sample proportion (p-hat), standard error, confidence intervals (Wald and Wilson), margin of error, and required sample sizes.
Ordering Numbers Calculator — Sort any set of numbers in ascending or descending order. Shows rank tables, quartiles, odd/even breakdown, grouping, and frequency distribution.
Pie Chart Calculator — Create pie charts from data with percentages, degree angles, SVG visualization, Herfindahl index, Shannon entropy, and cumulative breakdowns.
Parrondo's Paradox Calculator — Simulate Parrondo's paradox: two losing games that produce a winning strategy when combined. Adjust probabilities and see trajectory results.
Pie Chart Angle Calculator — Calculate the exact angle in degrees for each slice of a pie chart. Shows start/end angles, arc lengths, mid-angles, and step-by-step formulas.
Pie Chart Percentage Calculator — Calculate percentages for pie chart slices from raw data. Includes Pareto analysis, cumulative percentages, variation metrics, and step-by-step formulas.
Raw Score Calculator — Convert z-scores to raw scores using the population mean and standard deviation. Includes percentile lookup, distribution visualizer, and benchmark tables.
Point Estimate Calculator — Calculate point estimates for population mean, proportion, variance, and differences. Compare Wald, Wilson, Laplace, and Jeffreys estimators with confidence intervals.
Relative Error Calculator — Calculate absolute, relative, and percentage error between measured and actual values. Includes tolerance checking, error propagation, and visual comparison.
Rayleigh Distribution Calculator — Calculate PDF, CDF, quantiles, and moments for the Rayleigh distribution. Includes distribution visualization, survival function, hazard rate, and range probabilities.
Risk Calculator — Calculate expected loss, mitigation ROI, risk scores, and sensitivity analysis. Includes risk matrix, breakeven analysis, and visual risk gauge.
Relative Risk Calculator — Calculate relative risk, odds ratio, absolute risk difference, and NNT from a 2×2 contingency table. Includes 95% confidence intervals and chi-squared test.
Relative Standard Error (RSE) Calculator — Calculate the relative standard error, coefficient of variation, and quality rating for survey estimates. Includes confidence intervals and sample size planning.
Simpson's Diversity Index Calculator — Calculate Simpson's Diversity Index, Shannon Index, evenness, richness, and Hill numbers for any categorical dataset. Includes visual distribution bars and detailed breakdown.
Shannon Entropy Calculator — Calculate Shannon entropy, evenness, redundancy, perplexity, KL divergence, and Rényi entropy spectrum for any categorical distribution. Supports bits, nats, and hartleys.
Sample Mean & Proportion Calculator — Calculate sample mean or proportion with standard error, confidence intervals, hypothesis testing, and sample size planning. Includes Wilson interval for proportions.
Sum of Squares Calculator — Calculate sum of squares (SS), variance, and ANOVA decomposition. Shows SS total, SS between, SS within, F-statistic, and detailed deviation breakdowns.
T-Statistic Calculator — Calculate t-statistic, p-value, and Cohen's d for one-sample, two-sample (Welch's), and paired t-tests. Includes critical value table and distribution visual.
Two Envelopes Paradox Simulator — Simulate the two envelopes paradox with Monte Carlo trials. Compare switch vs keep strategies, visualize convergence, and understand the probability fallacy.
Mann-Whitney U Test Calculator — Perform Mann-Whitney U test (Wilcoxon rank-sum) with automatic ranking, tie correction, z-approximation, effect size, and detailed rank tables.
Upper Control Limit (UCL) Calculator — Calculate UCL, LCL, and center line for X-bar, R, S, p, np, c, and u control charts. Includes interactive control chart, SPC constants, and out-of-control detection.
Upper Fence Calculator — Calculate upper fence for outlier detection using the IQR method. Shows box plot, fence comparison at multiple k-values, and classifies every data point as normal, mild, or extreme outlier.
Upper & Lower Fence Calculator — Calculate both inner and outer fences for outlier detection. Shows box plot with dual fence boundaries, five-number summary, data classification, and distribution shape analysis.
Youden's Index Calculator — Calculate Youden's J statistic from sensitivity and specificity or a 2×2 table. Includes ROC space visualization, PPV/NPV, DOR, LR+/LR−, MCC, and a 13-metric performance dashboard.