Statistics, without the tears
Every calculator on this site was built around one idea: the working matters as much as the answer. Type in a dataset and you will not just get a standard deviation. You will see the deviation table that produced it, the formula it came from, and a worked example with ordinary numbers (bakery sales, quiz marks, a batsman's innings) before you trust it with your own.
Descriptive statistics
Mean, median, mode, standard deviation, variance, quartiles, IQR and the five-number summary. The toolkit for summarising any dataset.
Z-scores & percentiles
Convert between values, z-scores and percentiles, and read the standard normal table like a statistician.
All calculators
The complete index of statistics calculators, tables and learning guides on this site.
Learning guides
Plain-language explainers: population vs sample, p-values, error types, which test to use, and more.
Why students use these tools
- Steps, not black boxes. Every dataset calculator shows its working: the same tables you are expected to produce by hand.
- Formulas in the open. Population and sample versions side by side, with the reason for the difference explained.
- Private by design. Calculations run in your browser. Your data is never uploaded, stored or tracked.
- Free, forever. No sign-up walls between you and your homework.
Frequently asked questions
Are these statistics calculators free?
Yes. Every calculator, table and guide on this site is free to use, with no account and no limits.
Do the calculators show their working?
Yes. Dataset calculators display the intermediate steps (such as the squared-deviation table behind a standard deviation), so you can check homework or learn the method, not just copy an answer.
Is my data uploaded anywhere?
No. All calculations happen locally in your web browser; the numbers you type never leave your device.