Sample Size Calculator

This Sample Size Calculator is designed to help you estimate the sample sizes needed to attain a certain level of accuracy and confidence when planning a survey. Below are definitions of terms used when determining sample sizes.

  • Population Size refers to the total number of people in the organization or group that you want to study.

  • Confidence level represents the degree of certainty we want to have in the statistics.

  • Accuracy Range tells us how close to the true population value we want to be.

  • Adjusted Sample Size is the total number of surveys that need to be completed.

Determine Appropriate
Sample Size

What is the population size?

Do you want 85%, 90%, 95% or 99% confidence?

What is the range of accuracy you need?

%

Sample Size Required to attain this level:

0

What is the expected
return rate?

%

Adjusted Sample Size

 
 

Determined Accuracy of a
Given Sample Size

What is the population size?

What is the sample size?

Do you want 85%, 90%, 95% or 99% confidence?

Accuracy Range (plus or minus)

0%