What is this calculator used for?

Sample Size Calculator gives a quick formula-based estimate from the values you enter. Use it for sanity checks before quoting, ordering or planning.

Is this calculator free?

Yes. SectorCalc free calculators run in your browser with no sign-up required.

When should I use a premium analyzer?

Use a premium analyzer when the estimate affects pricing, operations or management decisions and you need hidden drivers, thresholds and export-ready reports.

Math & statistics

Sample Size Calculator

Finite population sample size from margin and confidence.

What is Sample Size Calculator?

Estimate required sample size for a finite population.

Enter values and calculate to see your result here.

Related calculators

How this calculator works

What this tool does

Finite population sample size from margin and confidence.

Formula summary

Statistical and math results apply standard formulas to the numeric inputs you provide.

What the inputs mean

Population (people): Population size Z score (z): Confidence z (e.g. 1.96) Margin error (%): Margin of error Proportion (%): Expected proportion

What this result includes

Formula-based estimate from the inputs you enter
Primary result plus supporting secondary values where applicable
Plain-language explanation of what the numbers represent

What this result does not include

Premium hidden-loss diagnostics or threshold verdicts
PDF or CSV export and saved report history
Professional financial, legal, medical or engineering advice

FAQ

What is this calculator used for?: Sample Size Calculator gives a quick formula-based estimate from the values you enter. Use it for sanity checks before quoting, ordering or planning.
Is this calculator free?: Yes. SectorCalc free calculators run in your browser with no sign-up required.
When should I use a premium analyzer?: Use a premium analyzer when the estimate affects pricing, operations or management decisions and you need hidden drivers, thresholds and export-ready reports.

How this calculator works

What this tool does

Finite population sample size from margin and confidence.

Formula summary

Statistical and math results apply standard formulas to the numeric inputs you provide.

What the inputs mean

Population (people): Population size Z score (z): Confidence z (e.g. 1.96) Margin error (%): Margin of error Proportion (%): Expected proportion

What this result includes

Formula-based estimate from the inputs you enter
Primary result plus supporting secondary values where applicable
Plain-language explanation of what the numbers represent

What this result does not include

Premium hidden-loss diagnostics or threshold verdicts
PDF or CSV export and saved report history
Professional financial, legal, medical or engineering advice

FAQ

What is this calculator used for?: Sample Size Calculator gives a quick formula-based estimate from the values you enter. Use it for sanity checks before quoting, ordering or planning.
Is this calculator free?: Yes. SectorCalc free calculators run in your browser with no sign-up required.
When should I use a premium analyzer?: Use a premium analyzer when the estimate affects pricing, operations or management decisions and you need hidden drivers, thresholds and export-ready reports.