DGR is a project file format used by DeltaGraph software. DGR are typically used for storing user-made diagrams. DGR format is supported by Apple and Microsoft operating systems.

DGR files offer access to over 80 types of diagrams for data visualization. The format has a very intuitive structure. License for DeltaGraph costs 299 USD. Last version of DeltaGraph (version 7) was released some years ago.