Sample Size Calculator
Survey planning: z²p(1−p)/e² with finite-population correction.
Required sample size
385 responses
- Uncorrected n₀
- 385
How the Sample Size Calculator works
The calculation follows the standard method used across the US — no shortcuts, no hidden assumptions. Here is exactly what happens behind the scenes:
Frequently Asked Questions
How does the Sample Size Calculator work?
Enter your numbers above and results update instantly using standard formulas, computed entirely on your device.
Is the Sample Size Calculator free to use?
Yes — completely free with no signup required, and it works on phones, tablets, and desktops.
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