Math & Science
Chi-Square Calculator
Perform chi-square tests for independence and goodness of fit
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Frequently asked questions
When to use chi-square?
For categorical data - testing if variables are independent or if data fits expected distribution.
What are the assumptions?
Expected frequencies should be at least 5 in each cell. Sample should be random.
How to interpret p-value?
If p < 0.05, reject null hypothesis - variables are likely related/distribution doesn't fit.
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About this tool
This Chi-Square Calculator turns your inputs into practical results. Provide Observed Values, Expected Values (optional), and Test Type to calculate P-Value and Chi-Square Statistic.
Adjust values to compare scenarios and see how sensitive the result is. The calculation uses the numbers as entered, so double-check units and expect small differences from rounding in the displayed totals.