Sample Size for Proportion Calculator
Estimate the required sample size for a population proportion from a z critical value, expected proportion and margin of error.
Estimate the required sample size for a population proportion from a z critical value, expected proportion and margin of error.
Move between confidence intervals, sample size, standard error, relative variability, correlation, regression and prediction error.
Calculate a z-based confidence interval for a population mean from a sample mean, standard deviation and sample size.
Open calculatorEstimate the required sample size for a population proportion from a z critical value, expected proportion and margin of error.
Calculate the standard error of a sample mean from standard deviation and sample size.
Open calculatorCalculate the coefficient of variation as standard deviation relative to the absolute mean.
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Open calculatorCalculate root mean squared error from the sum of squared errors and observation count.
Open calculatorSample Size for Proportion Calculator is an educational statistics and data-science tool for exploring a standard quantitative relationship.
Enter the requested values using the stated definitions. The calculator validates the numerical domain and applies n = z² p(1-p) / e².
Variables: z = Z critical value; p = Expected proportion (%); e = Margin of error (%).
Example: z = 1.96, p = 50%, e = 5% → n = 385 after rounding upward.
It is intended for study, classroom exercises and quick exploration of the stated statistical relationship.
No. Sampling design, assumptions, data quality, dependence, distribution shape, bias and model diagnostics may materially affect a real analysis.
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