Use this Marketing Sample Size Calculator to determine a sample size for testing the response to an upcoming B2B or B2C direct marketing campaign, or for a research survey in which you want to determine how many people to interview or send questionnaires (the minimum sample size).
The confidence level is expressed as a percentage and represents how sure you are that the actual percentage of the population who would respond lies within the percentage limit of error. The 95% confidence level means you can be 95% certain; the 99% confidence level means you can be 99% certain. Most researchers use the 95% confidence level. Greater confidence will generate larger sample sizes. This calculator is limited to confidence levels of 90, 95 and 99%.
Enter the percentage response rate as a whole number and / or decimal (i.e., 10 for 10%, 1.25 for 1.25%, .5 for .50 % of a percent, etc.)
The percentage limit of error is the plus-or-minus error amount or deviation (expressed as a percentage) that you are willing to tolerate from your projected response rate. For example, if you enter a 2% response rate and are willing to accept an error (or deviation) in response of 5% (i.e., response between 1.90% and 2.10%) at a confidence level of 95%, your sample size will be75,295. The range of error in this calculator is limited to a maximum of 15%.
To enter a value in any cell, click in the cell and you can use the number keypad to enter a number. To move to the next cell, click on the NEXT button in the keypad that appears. To reset this calculator to the initial zero values, click on the RESET button at the top of the calculator. You can open and close the individual panels as you enter values or leave them open to more easily conduct "what-if" analysis.