Collecting survey data on ego-centered social networks is a difficult task, owing to the complex questionnaire format. Usually, the interviewer handles the dynamics of the question–answer exchange, motivates the respondent and ensures the proper recording of the data. Self-administered modes of data collection, especially web data collection, are more problematic, as the respondents are left alone with a complex and burdensome questionnaire. Therefore, questionnaire layout is crucial for ensuring cooperation and data quality. In this paper we examined three key components of the corresponding web questionnaire: the number of name boxes using a single name generator, question format for assessing alter characteristics (i.e. alter-wise vs. question-wise) and number of name interpreters (i.e. alter characteristics). The number of name boxes was found to be essential for the reported size of social networks and also for some aspects of data quality. Specific data quality effects were also found with respect to variations in question format, where question-wise format performed better than alter-wise. The number of name interpreters had a relatively minor effect. Suggestions for possible standardization of the web interface layout are also given, so that equivalence with other data collection modes can be established.