Methods and user interfaces for generating level of detail calculations for data visualizations

A computing device displays a data visualization interface and receives user selection of a data source. The computing device also receives user input to select a measure data field and a dimension data field. In response to the user input, the computing device: generates a custom calculation that aggregates data for the measure data field, grouped by distinct data values of the dimension data field; and stores the custom calculation as a new selectable data field, associated with a data object corresponding to the dimension data field. The computing device also receives user selection of the new selectable data field and placement of the new selectable data field onto a first shelf in a shelf region. The first shelf defines a first data visualization characteristic determined according to data values of the custom calculation. The computing device generates and displays a data visualization based on the first data visualization characteristic.