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Z-test for Proportions-Independent Groups

This calculator is used to compare the proportions from two independent groups (i.e. groups with no overlap between them such as men and women) to determine if they are significantly different from one another. It allows you to enter the information for as many as 10 independent groups at a time. The calculator will then perform the Z-test for every possible combination of groups.

This test assumes you have a large population.

How To Interpret The Results

For example, suppose you carried out a survey with 200 respondents and you are interested in whether there is a difference between the observed results for males (Group 1) and females (Group 2), at the 95% confidence level.



Group 1 Group 2 Group 1 Group 2
Sample Size Group 1
Observed Sample Proportion Group 2

‘NO’ indicates that there is not a significant difference between the two observed proportions, i.e. the observed proportion for males is not significantly different to the observed proportion for females.



Confidence Level

The degree of confidence in whether or not the true figure for the population lies within the confidence interval for the survey.

For example, a 95% confidence level indicates there is a 1 in 20 (5%) chance that the true population result falls outside the confidence interval range.

Group 12345678910
Sample Size
Observed Sample Proportion ?

Observed Proportion (Enter as a %)

The % of respondents who gave the response you are interested in.


Use the calculator above to calculate your results.