Described is a system (and method) for application-based packing for storing backup data within an object storage. More particularly, the system may efficiently pack backup files into objects having a specialized size by accounting for the source and size of the backup file. For example, the system may determine whether backup files associated with a particular application may be stored within individual objects or packed together within a shared object. Accordingly, by accounting for such criteria the system may perform an intelligent allocation of backup data within a cloud-based object storage. The system may be implemented as part of an incremental backup infrastructure. Accordingly, when allocating the backup files amongst objects, the system may also store specialized metadata to preserve the ability to perform a reconstruction of data (e.g. synthetically) as if a full backup was performed.