Enter your data
Enter the number of subjects actually observed. Don't enter proportions, percentages or means.
Learn how to create a contingency table.
There are three ways to compute a P value from a contingency table. Fisher's test is the best choice as it always gives the exact P value, while the chi-square test only calculates an approximate P value. Only choose chi-square if someone requires you to. The Yates' continuity correction is designed to make the chi-square approximation better. With large sample sizes, the Yates' correction makes little difference. With small sample sizes, chi-square is not accurate, with or without the correction.
Fisher's exact test (recommended)
A P value can be calculated with either one or two tails. We suggest always using two-tailed (also called two-sided) P values.
Read more about P values
Chi-square with Yates' correction
Chi-square without Yates' correction