This calculator determines the sample size based on the confidence level, desired margin of error, and population standard deviation.

Sample Size Calculator for a Proportion

- First, input the confidence level, desired margin of error, and population standard deviation.
- Now press the 'Calculate' button.
- Finally, the tool shows the sample size required to estimate a population mean.

The sample size for a population mean is calculated using the following formula:

Sample Size (s) = (Z_{α/2} × σ/E)^{2}

Where,

Z_{α/2} = Z critical value associated with the confidence level,

E = Desired margin of error,

σ = Population standard deviation.