How long do respondents think online surveys should be? New evidence from two online panels in Germany

In recent years, the number of surveys, especially online surveys, has increased dramatically. Due to the absence of interviewers in this survey mode (who can motivate the respondents to continue answering), some researchers and practitioners argue that online surveys should not be longer than 20 min.

Corresponding author:

Melanie Revilla, Research and Expertise Centre for Survey Methodology, University Pompeu Fabra, Merce Rodoreda 24.406, Ramon Trias Fargas, 25-27, 08005 Barcelona, Spain. Email:


Previous research suggests that comparatively long surveys are associated with several negative effects, especially in the case of online surveys. For instance, Crawford et al. (2001) and Marcus et al. (2007) found that a longer announced survey leng