Two-sample Kolmogorov-Smirnov test calculator
Paste two independent samples. The calculator compares their empirical CDFs at every observed point.
Empirical CDFs
| x | F_A(x) | F_B(x) | |F_A − F_B| |
|---|---|---|---|
| Fill in the fields above — the result is computed on this page. | |||
How do I use this page?
- Paste two independent samples.
- Find the largest CDF difference in the table.
- Read D and the approximate p-value.
What this page does not do: The classical test assumes independent observations from continuous distributions. Many ties or discrete data change the statistic distribution; a permutation procedure or a method designed for discrete data is then preferable.
Further reading
Theory — what is the two-sample Kolmogorov-Smirnov test?
The two-sample Kolmogorov-Smirnov test measures the largest vertical distance D between two empirical distribution functions built from two independent samples. Because it compares entire distributions rather than just means, it can detect differences in location as well as in spread or shape. The calculator computes the D statistic at every observed point and derives the p-value from it.
Frequently asked questions
Does the test compare only means?
Are ties allowed?
See also
A/B test calculator
Compare two proportions in an A/B test. Calculate conversion rates, difference, uplift, z score, p value and c
A/B test planning — sample size, MDE and duration
Plan a two-proportion experiment, estimate detectable effect and traffic duration.
ACF and PACF autocorrelation calculator
Calculate ACF and PACF across time-series lags. Review the chart, reference bounds and coefficient table.