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Sample Size Calculator

Required n for a survey.

Sample size

Required n
383
0.4% of population
Without finite-population correction
385
What you'd use for an effectively infinite population
z-score used
1.960
For 95% confidence
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Sample Size Calculator · Generated 5/2/2026 · calccenter.online/calculators/math/sample-size

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About the Sample Size Calculator

MethodologyHome

Required n for a survey. Use this free sample size calculator to get instant results. All calculations run in your browser — nothing is sent to a server.

Frequently asked questions

What does this Sample Size Calculator do?

Required n for a survey.

Is it free?

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