Three properties that most copy-and-paste backups lack: data is encrypted before it leaves the machine, snapshots store only what changed, and the archive can be checked whenever you like.

Running out of backup space? The deduplication in BorgBackup is the direct answer: identical chunks are stored once, incremental runs finish quickly, storage use drops by a wide margin, encryption and compression come together, and the open source command line approach has been trusted by server administrators for years.

Kopia is an open source backup tool that keeps snapshots, encrypts data before it leaves the machine and stores it on almost any backend, with both a graphical front end and a command line interface.

Duplicati is a free, open-source backup tool that encrypts with AES-256 on the machine before anything leaves it, then uploads blocks to storage you already own: object storage, WebDAV, an FTP server, even a local disk. The 2.4 stable release, out on 3 September 2026, extends whole-disk imaging from Windows to Linux and macOS, adds a one-way sync mode and verifies volumes against bit rot.

Deja Dup turns backup into a few choices on the desktop: what to save, where to put it, and how often, with encryption and incremental copies underneath.

A closer look at the recovery pair: TestDisk restores partitions and keeps file names, while PhotoRec ignores the file system and carves data by signature, so a formatted partition can still give files back. This covers the 7.3 development line and the options that change the result.

The free edition of DMDE 4.4.4 recovers up to 4000 files from a chosen directory, with no limit on how many attempts are made. The paid editions lift the cap and add disk editing, partition management and RAID construction.

TestDisk and PhotoRec 7.2 were released on 2024-02-22 and are entirely free and open source. The first specialises in repairing partition tables and finding lost partitions, the second pulls files out of damaged media by signature.