For Accurate Survey Findings, Use our Sample Size Calculator

If you want to forecast how your customers or employees feels and think, you'll need to calculate the sample sizes you will need first.

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Martha Brooke, CCXP & Six Sigma Black Belt, recommends the best methods for your objectives.

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Use our Survey Sample Size Calculator to find the right sample size for your survey.

Once you know your margin of error and confidence level, you can calculate the sample size you need to achieve statistically valid results. Try it out!


The basic  terms you need  to use our survey sample size calculator:

  • Margin of error: The lower your margin of error, the more accurate your results will be. A 5% margin of error is often used in polling studies, and it’s generally the norm. Just keep in mind that a 5% margin of error is a 10% spread because you could be plus OR minus 5%.
  • Confidence level. Statisticians often refer to a confidence level, and here is a simplistic explanation. Let’s assume you set your confidence level to 95%. If you were to repeat your experiment over and over again, the results would match the results from the actual population 95% of the time, or 19 times out of 20.
  • When you combine your margin of error (for example, 5%) and your confidence level (for example, 95%), you can say that you are 95% sure that the true measurement of the general population is within 5% of your survey results.

Read more about how to use a survey sample size calculator here.

Why Sampling Matters

Your staff is more likely to get on board with your recommendations if your data represents your customer base proportionately.

Think of it this way: If you were running a large health study, you’d make sure your sample included multiple ethnicities and health profiles. Similarly, your data should represent the entirety of your customer base, not just those with free time, a gripe, or who provided their email.


Get a Free Consulting Session ➔

Martha Brooke, CCXP & Six Sigma Black Belt, recommends the best methods for your objectives.

  • This field is for validation purposes and should be left unchanged.