.R1 File Extension
WinRAR Multi-Volume Archive Part 1
2.0 | 5 Votes
What is an R1 file?
Archive file that is part of a RAR multi-volume archive; contains part one of a compressed volume; stores a compressed part or fragment of a larger file; may use the extensions R0 through R99.
WinRAR creates multi-volume archives and can build them back into the original file.