About StatsMasters

A useful place to start

Use the statistical tables for probabilities and critical values, the calculators to work with your data, and the lessons to understand the methods. Our guides help connect those steps.

How the content is checked

The core lessons connect formulas to worked examples, assumptions, and conclusions in the original units. References link to sources such as the NIST statistical handbook and official statistical software documentation. Hypothetical datasets are labeled as teaching examples; several are available to download and reproduce.

Numerical checks independently verify the printed distribution tables and selected worked examples against SciPy. These checks establish arithmetic consistency, not the suitability of a method for every dataset. Lesson self-checks and the guided analysis are practice, not graded assessments. Guided practice explains every answer choice and can save progress in your browser.

Follow a suggested reading path , practice a full analysis, or expand a term in the glossary for a practical example. The helpfulness buttons let readers flag explanations that need more work.

Free tools, no account required

The tables, calculators, and lessons are available without an account. Calculations run in your browser.

Understanding comes before a conclusion

Every statistical method has assumptions. Check your study design, the distribution of your data, and what your result actually says. Use the site as a learning aid and compare important calculations with a trusted statistical package.

Choose a method · Open the formula reference · Read about analytics