rsync, FreeFileSync, Duplicati, SyncToy, GoodSync, DirSync Pro, Syncovery, Bvckup 2, luckyBackup, MirrorFolder, Yadis! Backup, csync, Areca Backup, Personal Backup, Syncrify, SSuite File Backup Master, FileFort Backup Software, Stellar Insta Backup, AutoArchive, AnyBackup, Z-DBackup, SmartBackup, FastBackup are some alternatives to FBackup.