# Sample Size Calculator

Free online statistics calculator that helps you to determine the number of experimental units required for the survey with the given confidence interval, level and population size.

## Sample Size Calculation

95% 99%

95% 99%

#### Confidence Level:

Free online statistics calculator that helps you to determine the number of experimental units required for the survey with the given confidence interval, level and population size.

Code to add this calci to your website  #### Formula:

Sample Size = ( Z^2 * p * ( 1 - p ) ) / m^2 Confidence Interval (m) = sqrt(( Z^2 * p * ( 1 - p ) ) / Samplesize) Where, Z = Confidence Level (E.g. 1.96 for 95% Confidence Level), p = Worst Case Percent (Default Value: 0.5), m = Margin of Error (or) Confidence Interval. If Finite Population, Sample Size for Finite Population = Samplesize / ( 1 + ( ( Samplesize - 1)/Population) ) Confidence Interval (m) = sqrt(( Z^2 * p * ( 1 - p ) ) / Samplesize)

Compute the critical value for the normal distribution using this online sample size calculator.