It is possible to calculate medians using the Online Data Analysis System by checking the “Summary statistics” option on the “Frequencies/Crosstabulation” screen; however, there are two exceptions where this is not possible. First, you cannot include a Column variable. Instead, you would need to enter this variable as a Control variable to create separate tables for each value of your desired Column variable. Second, it is not possible for the online analysis tool to generate the median if the number of cells exceeds the limit (see this previous answer for a solution).
Hope this helps.