A UFR file is a data file used by Upfiring, a peer-to-peer (P2P) file sharing application, to download one or more files uploaded by other users. It does not store the actual content but instead contains encrypted metadata, which includes information about the file(s) being shared, the price of the file(s), and the owner of the file(s). UFR files are similar to .TORRENT files, which are used by BitTorrent and other P2P file sharing programs.

Upfiring is an Ethereum blockchain-based P2P program that gives UFR tokens to users that upload files to the network and "seed" the files, which is when users stay connected to the network to help distribute files to other users. By incentivizing users to become "seeders," Upfiring is able to offer a more robust network of users, which results in quicker download times and more available files for download. Upfiring administers all transactions between users using smart contracts, which allows users to send Ether (the Ethereum digital currency similar to Bitcoin) to other users. Users must add an Ethereum wallet in the Upfiring application to properly complete transactions. To create a UFR file in Upfiring, select the "Uploads" icon in the left pane then click Upload. After uploading the UFR file, other Upfiring users can access the UFR file to download shared files. To import a UFR file in Upfiring, select the "Downloads" icon in the left pane and drag and drop the UFR file or browse files on your computer to select the UFR file. NOTE: You can view the contents of a UFR file using simp.io UFR Viewer.