Statistics, calculated clearly.
Free statistics calculators with step-by-step solutions and APA-formatted output. Hypothesis tests, regression, probability, z-tables and more. Built for Researchers, students and analysts.
See every step
See your answer with complete solution, showing every calculation, so you can solve exam questions with confidence.
Real formulas
Every result is backed by the same formulas that are taught in statistics textbook, explained in plain English, so you can use them in your research and exams.
Free, no sign-up
Enjoy all 21 calculators made for you, no sign-up, easy to use on any device. Nothing gets in your way.
Reviewed for accuracy
Every method is checked against standard textbook definitions and reviewed regularly for correctness.
Calculators
21 statistics calculators covering descriptive statistics, regression, hypothesis testing, and probability each with step-by-step solutions and formulas
Descriptive statistics
Summarize and describe a data set.Standard Deviation
→Sample & population standard deviation with steps.
Variance
→Population & sample variance with steps.
Percent Variance
→Variance between two numbers: percent change & difference.
Mean, Median, Mode
→The core measures of central tendency, instantly.
Coefficient of Variation
→Compute %CV from data or mean and standard deviation.
Percentile & IQR
→Quartiles, IQR, percentiles, and a box plot.
Skewness
→Measure distribution asymmetry.
Kurtosis
→Excess kurtosis (sample & population).
Correlation & regression
Model relationships between variables.Inference & hypothesis testing
Draw conclusions and test claims.P-Value
→Find p-values from a test statistic, with interpretation.
Confidence Interval
→CI for a mean using the z- or t-distribution.
Hypothesis Test
→One- and two-tailed tests with a decision.
Difference in Means
→Compare two population means.
Sample Size
→Required sample size for a survey or study.
Chi-Square
→Goodness-of-fit and independence tests.
One-Way ANOVA
→Compare the means of three or more groups.
Probability & distributions
Work with chance and the normal curve.Statistical tables
Critical values & how to read them.How it works
From raw numbers to a result you understand in three steps.
- 1
Enter your data
Paste a column from Excel or a CSV, or type your numbers straight in. Most calculators accept commas, spaces, or new lines.
- 2
Get instant results
Results update the moment your data changes the meaning, standard deviation, test statistic, p-value, or interval you need.
- 3
See every step
Expand the step-by-step solution to see the formula, the substituted values, and a plain explanation of what the result means.
Built for students, researchers & analysts
Whether you’re checking homework or a published result, every step is always in view.
Students
Verify your homework and learn the method, not just the final number perfect for exam prep and statistics coursework.
Researchers
Accurate, citable results with transparent formulas and assumptions, so you can trust what goes into your paper.
Analysts & professionals
Fast, reliable calculations for everyday analysis with the reasoning behind every answer, in seconds.
Frequently asked questions
Are these statistics calculators free?+
Yes. Every calculator and reference table on Statistics Inference is completely free and unlimited. There is no account to create, no paywall, and no limit on how many calculations you run.
Do the calculators show step-by-step solutions?+
Every calculator shows the full working the formula used, your values substituted into it, and a step-by-step solution alongside a plain-English explanation of what the result means.
What is the difference between sample and population standard deviation?+
Population standard deviation divides by n and is used when your data covers the entire group of interest. Sample standard deviation divides by n − 1 (Bessel’s correction) and is used when your data is a sample drawn from a larger population. Our calculators report both so you can pick the right one.
Can I use these calculators for homework or research?+
Yes. The methods follow standard textbook definitions and are reviewed for accuracy, and each result shows the formula and steps so you can verify the step by step and cite the method in your assignment or paper.
Do I need to install anything?+
No. Everything runs in your browser on any device desktop, tablet, or phone. There is nothing to download or install.
How accurate are the results?+
Calculations use full floating-point precision and the standard statistical formulas, with results rounded only for display. The library of methods was last reviewed for correctness in Oct 2026.
Ready to run the numbers?
Pick a calculator and get an accurate answer with every step shown in seconds.