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Sample Size Calculator

Estimate a survey sample size from confidence, margin of error, and population.

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Recommended sample size
385
95% confidence, ±5% margin of error
Unadjusted sample size385
Finite population correctionNot applied
Expected proportion50%

Normal approximation for a proportion, assuming a random sample. Sampling design effects and nonresponse are not included.

About the Sample Size Calculator

Estimate a survey sample size from confidence, margin of error, and population.

It runs entirely in your browser — nothing you type is sent to a server — and the result updates as you edit the inputs. Estimates are for educational and informational purposes only; see ourdisclaimer.

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