Sampling Calculator

Count ordered and unordered samples with or without replacement.

Sample Size Calculator

Fill in the fields below to calculate

Population Size (N)

Leave empty for large populations

Confidence Level

Margin of Error (E) %

Proportion (p)

0.5 for maximum variance

Enter your values above to see the result.

Your Results

Required Sample Size

Z-Score

Formula

Infinite Population:

n = Z² × p × (1-p) / E²

Finite Correction:

n_adj = n × N / (n + N - 1)

Z-scores: 90%=1.645, 95%=1.96, 99%=2.576

Pro Tips

Results update as you type — change any field to see the effect immediately.

Check that every value uses the same unit before comparing results.

Use the copy button to paste the sampling figures into a note or spreadsheet.

Nothing is sent to a server, so you can use this with private figures.