# Free Survey Sample Size and Invites Required Calculator

You can use our free survey sample size calculator to quickly determine the sample size required based on the population and margin of error decisions. In addition, this calculator will provide the number of survey invitations required to achieve the survey sample size based on the estimated response rate.

## Survey Sample Size and Invites Calculator

The population is the number of people you are trying to study. A population is finite if there are a countable number of people in the population. Conversely, if the people in a group are not countable, it is an infinite population. An infinite population can be assumed for populations larger than 20,000. The finite population calculator should be used for populations less than 20,000, such as employee studies.
Sample Size Calculator
To determine the required sample-size that is necessary within an infinite population, enter the margin of error number below (e.g., a good rule of thumb for the sample size to be statistically accurate is a margin of error of ± 5.0):
%
Note: Margin of error is calculated at the 95% confidence level.
Survey Invitation Number
What percentage of those asked will participate in the post-contact customer survey? The typical post-contact customer survey response rate is 3% to 10%, and the employee survey response rate is 50% to 95% but will vary by survey method, contact list quality, customer type, etc.
%
%
Margin of Error Calculator
To calculate the margin of error resulting from a specific sample-size, enter that sample size below:
#
Note: Margin of error is calculated at the 95% confidence level.
The population is the number of people you are trying to study. A population is finite if there are a countable number of people in the population. Conversely, if the people in a group are not countable, it is an infinite population. An infinite population can be assumed for populations larger than 20,000. The finite population calculator should be used for populations less than 20,000, such as employee studies.
Sample Size Calculator
To determine the required sample-size that is necessary within a finite population, enter the population size and margin or error, enter the numbers below (e.g., a good rule of thumb for the sample size is a margin of error of ± 5.0):
#
%
Note: Margin of error is calculated at the 95% confidence level.
Survey Invitation Number
What percentage of those asked will participate in the post-contact customer survey? The typical post-contact customer survey response rate is 3% to 10%, and the employee survey response rate is 50% to 95% but will vary by survey method, contact list quality, customer type, etc.
%
%
%
Margin of Error Calculator
To calculate the margin of error resulting from a specific sample-size drawn from a defined population, enter that sample size and population amount below:
#
#
Note: Margin of error is calculated at the 95% confidence level.