Test whether two categorical variables are associated using a 2×2 table of observed counts — for example, whether passing an exam is related to attending a workshop.
How to use it
Enter the four cell counts from your contingency table. The calculator computes the expected counts, the chi-square statistic and the p-value for you.
How to read the result
A p-value below 0.05 indicates a statistically significant association between the two variables. If any expected count falls below 5, the calculator warns you, because Fisher’s exact test is more appropriate for very small samples.
Rather have it done for you?
Send us your data and a qualified statistician will run the analysis and write it up. Fixed price, by email.
Frequently asked questions
What is a chi-square test of association?
It checks whether two categorical variables are related by comparing the counts you observed against the counts you would expect if the variables were independent. A large gap between observed and expected produces a large chi-square and a small p-value.
What if my expected counts are small?
When expected counts drop below 5, the chi-square approximation becomes unreliable. Use Fisher’s exact test instead — the calculator flags this automatically.
Can I test a bigger table than 2×2?
This tool handles the common 2×2 case. For larger contingency tables, send us your data and we will run the full analysis for you.