Sample Size Calculator

Find out how many survey responses you’ll need to have the desired level of accuracy in your results.

Calculate your sample size

Sample size

?

Choose from millions of respondents right now with Consumer Panels

Understanding sample sizes

It’s something most researchers understand that the larger your sample size the more accurate your data is going to be to that for the population as a whole. But it’s harder to understand just how large the sample needs to be to give a certain level of accuracy.

Knowing how big your sample needs to be to get a given level of accuracy is very important if you’re planning to buy consumer panels, for instance.

Surveys with a too-small sample for the population size can give misleading answers, so it’s always critical to maximise the sample size where possible, and to always bear in mind that there’s always a margin of error.

Calculating sample size manually

We’ve provided an automatic calculator for this, but as any good researcher and student knows, it’s important to show your working.

The sample size is defined by the formula illustrated.

After crunching all those numbers, (or using our calculator, if you’re smart), you’ll find a number that defines how many responses you need to receive for your survey to meet the criteria you’ve set for it. By playing around with the numbers (and looking at the equation) you may notice that the required sample doesn’t increase linearly with the desired measures of accuracy, with the required samples getting very large.

So, now you should be armed with all the information and numbers you need to determine how many responses you need to be able to have real confidence in your results.

Explore our paid plans to unleash the full potential of SmartSurvey

Our survey software is user friendly yet packed full of advanced features. Find out how our platform can deliver the results you need.

Self-service

Get started with all the tools you need to quickly create great looking surveys and start collecting feedback.
Select your plan

Enterprise

Access our most advanced tools, features and integrations to power your feedback activities and drive change.
Find out more