Embodiments relate to ideal age vector based file retention in a software testing system. An aspect includes determining an ideal age vector of historical bug age data corresponding to a software product in the software testing system, wherein the software testing system stores a plurality of version files of the software product. Another aspect includes based on receiving a new version file of the software product, determining a file to delete of the plurality of version files and the new version file based on the ideal age vector. Yet another aspect includes deleting the determined file to delete such that a number of remaining version files is equal to a number of the plurality of version files.