Interactive Sample Calculator

We have provided these sample calculators for you to use to determine key factors for your survey. You will be able to calculate what your error margin will be based upon the number of people you survey or conversely how many people you will need to interview for a particular error margin level.

Definitions

Population Size:
The total number of people in the population. i.e customers, prospects, etc.

Sample Size:
The number of people in the survey. The "plus or minus" amount, or percentage in the case of estimating proportions.

Confidence Level:
The degree to which you are certain that the result, or estimate, you obtain from the study includes the true population percentage, when the precision is taken into account. The most common confidence level is 95%, although any confidence level can be used.

Error Margin:
The level of precision (+/-) for a sample within a specified confidence level (e.g. 95%).

Error Margin Calculator
Enter in the total population and sample size in this calculator it will produce the Error Margin for a confidence level of 95%.