Statistics Calculator
Run the statistics you need for coursework or research — from standard deviation to t-tests and ANOVA — with data from Excel or CSV.
- Your data never leaves your device
- 100% free
- No sign-up
- Works offline after first load
How to use the statistics calculator
- Choose the kind of analysis.
- Paste your data or enter the values.
- Read the results, chart and explanation, and copy them into your report.
About Statistics Calculator
A complete statistics calculator for students and researchers.
It works in your browser, so it is instant and private, and your details are remembered on this device.
Good for
- Homework and exams in statistics
- Lab reports and research projects
- Quick data checks at work
Tip: Copy a column from Excel or Google Sheets straight into the data box — spaces, commas and line breaks all work.
Frequently asked questions
How do I calculate standard deviation?
Paste your numbers into Descriptive statistics. You get the sample standard deviation (dividing by n − 1, like Excel’s STDEV.S) and the population standard deviation (dividing by n, like STDEV.P), with the variance, quartiles and more.
How is the p-value of a t-test calculated?
From the t statistic and the degrees of freedom with the exact Student t distribution. The two-tailed p-value is twice the area beyond |t|. If it is smaller than α (usually 0.05), the result is statistically significant.
Which t-test should I use?
One-sample to compare a mean with a fixed value, the two-sample (Welch) test for two independent groups — it does not assume equal variances — and the paired test for before-and-after measurements on the same subjects.
How do I find a probability with a z-score?
Choose Normal distribution, enter the mean, the standard deviation and x. You get the z-score, the probability below, above or between values, and the curve with the area shaded.
Do the results match Excel, SPSS or R?
Yes. Standard deviation, quartiles (QUARTILE.INC), skewness and kurtosis match Excel, and t-test p-values match T.TEST, R and SPSS.
Can I run ANOVA or chi-square tests?
Yes. Choose ANOVA and enter one group per line to get the full table with F, p-value and η². Choose Chi-square test and type a table of counts to get χ², the p-value, Cramér’s V and the expected counts.
How big should my survey sample be?
Choose Sample size, set the confidence level and margin of error, and optionally the population size. For ±5% at 95% confidence you need 385 responses from a large population.
Is my data uploaded?
No. Numbers you type and files you open (CSV, Excel or text) are read and calculated in your browser. Recent calculations are kept only in this browser (History).