Enter N (leave blank if not known) Enter n (leave blank if not known) Enter Reliability % Enter Variability %

##### How does the Proportion Sample Size Calculator work?
Free Proportion Sample Size Calculator - This calculator determines a sample size to select to meet certain criteria related to a confidence percentage, reliability percentage, and a p value proportion. Simply enter your values not using percentage signs. This works whether p^ is known or not known.
This calculator has 4 inputs.

### What 3 formulas are used for the Proportion Sample Size Calculator?

p = n/N
α = 1 - Confidence%
Sample Size = Z-score2 x p x (1 - p)/SE2

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##### What 4 concepts are covered in the Proportion Sample Size Calculator?
proportion
n equation in which two ratios are set equal to each other
a/b = c/d
proportion sample size
reliability
the overall consistency of a measure
sample size
measures the number of individual samples measured or observations used in a survey or experiment.