1. A computer implemented system that determines costs associated with updating file formats, the system comprising at least a processor and a memory, and further comprising: an interface component that interfaces with a network-accessible data storage service that facilitates archival of data associated with a user and retrieval of archived data; a monitor component that examines the archived data, and monitors archival transactions and retrieval transactions involving the data storage service, the monitor component identifying a legacy file formatted in a legacy format without the user being aware of a location of the legacy file, the monitor component identifying the legacy file based upon detection that the legacy file is configured in the legacy format, the monitor component further selecting plural optimal converters from a set of converters according to an optimal path, the selection comprising selecting a first optimal converter for converting or migrating the legacy file from a legacy file format version to an intermediate file format version, and a second optimal converter for converting or migrating the legacy file from the intermediate file format version to an updated file format version; a catalog component that determines the optimal path from a plurality of paths for constructing the updated file from the legacy file; and an analysis component that determines a respective cost-benefit to the data storage service for each of a plurality of conversion scenarios utilizing optimal converters for migration or conversion of the legacy file to an updated file with an updated format, the migration replacing the legacy file with the updated file and the conversion constructing the updated file that is distinct from the legacy file and upon determining a cost-benefit analysis, the analysis component facilitates creation of the updated file from the legacy file using the selected plural optimal converters.