Sample Size Calculator

Minimum sample size for estimating a proportion — margin of error, confidence level, optional finite population correction.

Also available in 한국어

Expected proportion p (%)0.5 is the most conservativeMargin of error (±) (%)Confidence levelPopulation size (0 = infinite)

The amounts you entered are included in the link. Anyone with the link sees the same result.

Minimum required sample

1,068

How it was calculated

01Base sample size (infinite population)
n = z²·p(1−p) / e² = 1.96² × 0.5 × 1 / 0.03²
Basis: Sample size formula for a proportion (normal approximation, Wald)
1,067.1111
02Minimum required sample = 1,068
Rounded up
Basis: Sample size is rounded up to an integer
1,068

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