It’s not surprising that the length of a survey can sometimes have a negative impact on your survey completion rate. It’s pretty intuitive—the longer a survey takes to complete, the higher your chances may be of people dropping out.
So it’s a delicate balance of achieving your research goal, while also ensuring that people take your survey from beginning to end.
In general, keeping your survey concise can improve survey completion rate. However, there are situations where more questions are critical to a survey’s success.
For example, when companies are taking part in a big internal initiative like measuring culture, typically their employee engagement surveys tend to be on the longer side because there’s a lot to cover. So if you know you have a longer survey to send out, just how many questions should you ask respondents to in order to optimize your survey completion rate?
Well, we are of course big fans of analyzing data at SurveyMonkey. Here’s some completion rate data to help you estimate how many survey takers you need to reach when sending longer surveys.
We analyzed the completion rate of 50,000 random surveys conducted by SurveyMonkey users and aggregated the data based on the number of questions in the surveys. You can use the table below to get an estimation of how many respondents you need to reach out based on the length of your survey:
In order to figure out how many people you need to send your longer survey to, first look at the completion rate based on the number of questions in your survey. Then you can calculate the total number of people you need to send your survey to like this:
Number of Respondents You Need = Desired Completes / Expected Complete Rate
For example, if you have a long survey with 46-50 questions and you want to collect at least 100 completed responses, on average, you will need to send your survey to about 117 (100 / .852) survey takers.
There you have it, data fans. We hope this comes in handy the next time you’re designing your survey and don’t be shy—let us know if you have any questions on this chart or more in the Comments section below.
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