The *z*-score test for two population proportions is used when you want to know whether two populations or groups (e.g., liberals and conservatives) differ significantly on some single (categorical) characteristic - for example, whether they watch *South Park*.

To use the calculator, just input the proportions (or absolute numbers) for your two samples in the textboxes below, together with the size of each sample. Then press the "Calculate Z" button.

Sample 1 Proportion (or total number)

Sample 1 Size (*N _{1}*)

Sample 2 Proportion (or total number)

Sample 2 Size (*N _{2}*)

Significance Level:

One-tailed or two-tailed hypothesis?:

No calculation performed yet.