Margin of Error Calculator, With FPC

Margin of error for a survey proportion, with and without the finite population correction, plus the sample size hiding behind any headline poll number.

Population size N

Sample size n

Confidence level

Expected proportion p

Calculating…

Margin of error vs. sample size. Orange applies the finite population correction; gray ignores it. The marker shows your sample.

Assumption check

For estimating a single proportion from a simple random sample. The correction matters when the sample is more than five percent of the population.

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