Statistics Tools
Choose a calculator for formulas, live results, charts, examples, FAQ, glossary and references.
- Mean Median Mode Calculator
Mean median mode calculator for central tendency, range, quartiles, variance and standard deviation with live chart, formulas and steps.
- Standard Deviation Calculator
Standard deviation calculator for sample and population SD with variance, mean, deviations, formulas, chart and step-by-step working.
- Variance Calculator
Variance calculator for sample s squared and population sigma squared with coefficient of variation, formula, chart and steps.
- Z Score Calculator
Z score calculator for z=(x-mu)/sigma, percentile from normal CDF, reverse x from z, formula and bell curve.
- P Value Calculator
P value calculator from Z, t, chi-square and F statistics with one-tailed and two-tailed results, formulas and interpretation.
- T Test Calculator
T test calculator for one-sample, Welch two-sample and paired tests with t statistic, df, p-value, effect size and steps.
- Confidence Interval Calculator
Confidence interval calculator for means and proportions using z or t critical values, margin of error, formula and steps.
- Probability Calculator
Probability calculator for union, intersection, conditional probability, complement and normal CDF with formulas and Venn chart.
- Sample Size Calculator
Sample size calculator for means and proportions with confidence level, margin of error and finite population correction.
- Combination Permutation Calculator
Combination permutation calculator for nCr, nPr, repetition formulas and factorials using BigInt for large exact integers.
- Chi Square Calculator
Chi square calculator for goodness-of-fit and contingency table independence tests with p-value, df and steps.
- Correlation Coefficient Calculator
Correlation coefficient calculator for Pearson r, Spearman rho, t test, p-value, strength interpretation and scatter plot.
- Linear Regression Calculator
Linear regression calculator for simple OLS best-fit line, slope, intercept, R squared, prediction and scatter plot.
- Margin Of Error Calculator
Margin of error calculator for means and proportions with confidence level, z critical value, formula and interpretation.
- Five Number Summary Calculator
Five number summary calculator for min, Q1, median, Q3, max, IQR, fences, outliers and live box plot.
What these statistics tools do
The statistics tools help calculate descriptive statistics, probability, confidence intervals, hypothesis tests, regression, correlation, combinations, permutations, and sample-size estimates. Each tool shows the formula and a worked interpretation so the result is easier to verify.
How to use the statistics tools
- Choose the calculator that matches the statistic or test you need.
- Enter raw data or summary values in the requested format.
- Check the formula, assumptions, p-value or interval, and interpretation before reporting the result.
Sources and References
What this collection does
This page groups related statistics tools so visitors can choose the right calculator or converter without guessing from a filename alone. The links, summaries, and supporting notes explain what each page is for and what kind of input it expects.
How to use this collection
- Start with the tool that matches the measurement, tax topic, network task, or text operation you need.
- Open the matching page and check the input labels, examples, and assumptions before entering data.
- Use the result as a practical calculation aid, then verify high-impact work against official rules, source records, or domain references.
Frequently Asked Questions
Is Statistics Tools free to use?
Yes, Statistics Tools is completely free with no signup required. It runs entirely in your browser, so you can use it as often as you need.
How accurate is Statistics Tools?
Statistics Tools uses standard, well-established formulas to provide accurate educational results. For complex or critical decisions, consult a qualified professional.
Is my data private?
Yes. All calculations happen locally in your browser. Your inputs are not uploaded, logged, or stored on our servers.
Does Statistics Tools work on mobile?
Yes, Statistics Tools is fully responsive and works on phones, tablets, and desktop browsers without any installation.
Which statistics calculator should I start with?
Start with descriptive tools such as mean, median, standard deviation, or five-number summary when exploring data. Move to confidence intervals, p-values, regression, or chi-square only after the question and assumptions are clear.