Techniques are disclosed relating to providing customized user interfaces to different groups of users. A computing system may determine a plurality of different design types for a user interface and cause display of user interfaces that exhibit the different design types to different users. Based on user interactions with the user interfaces, the system may generate one or more metrics. The system may and may determine attribute values for attributes of users who interact with the user interface. The system may perform one or more correlation procedures to correlate the attribute values with one or more of the metrics. In disclosed embodiments, the computing system generates groups of users based on the correlation. The computing system may assign at least one of the design types to at least one of the groups of users based on the correlation.