Survey Sample Size Calculator
The number of valid questionnaires required for estimates based on confidence levels, error ranges, expected ratios, and overall size.
Survey Sample Size Calculator User manual
- Fill in the parameters or select the file according to the form, and check the unit and format first.
- 95% confidence level, 5 percentage points error, and expected ratio of 50%, estimated effective sample number.
- Click the processing button to view the results, you can copy or download and save.
Calculation method and processing rules
Estimate a proportion's sample size using a normal approximation, apply the finite-population correction and round up, then estimate invitations.
scope of use
It is suitable for estimation of ratio of simple random sampling; it is not used for two groups of test efficacy, complex sampling or elimination of selection deviations, and the response rate is only a planned hypothesis.
Will the input content be saved on the server?
This tool handles input in the browser, and does not upload files or form content. Typing practice scores are only saved in the native browser.
Why may the result be different from other tools?
It is suitable for estimation of ratio of simple random sampling; it is not used for two groups of test efficacy, complex sampling or elimination of selection deviations, and the response rate is only a planned hypothesis. Please compare the input unit, rounding method, applicable rules and data version first.