Box Backup

Free plan LinuxMacSelf-hostedWindows

What Box Backup is

Box Backup is a free, open-source system for automatic online file backup. Clients are listed for Linux, Windows, macOS, and other Unix systems, while the backup server runs on Unix. The client detects changes, encrypts files, and transfers only changed portions, including changes within files. Older versions and deleted files remain available, and the bbackupquery utility can query and restore backup data. TLS protects connections and authenticates servers and clients with certificates; stored file data uses AES and metadata uses Blowfish. Users must keep a 1k key file safe because the server data cannot be decoded without it. Backed-up data is stored as files on a filesystem and compressed, with no tape or archive devices required. Backup behavior can target document or server use, and traditional snapshots are possible. The system includes a backup store server, client daemon, and restore tool. Housekeeping may remove deleted client files quickly, so archived files may need another arrangement.

Who it suits

Box Backup fits users wanting free, self-hosted file backups across Linux, Windows, macOS, or Unix clients. It is also suited to operators who can run a Unix backup server and protect the required key file.

What it does well

Free and open source
Transfers only changed file portions
Retains older versions and deleted files
TLS and encrypted stored data
Supports self-hosted filesystem storage

What to know first

Unix is required for the backup server
Windows servers are highly not recommended
Housekeeping may remove deleted files quickly
Users must safeguard a 1k key file

Plans

Plan	Billed and limits	Price
Box Backup	open source · self-hosted backup server	Free

As boxbackup.org lists them, read 11 Oct 2026. The maker's own page has the final word.

Verdict

Box Backup provides encrypted, incremental file backup with version history and self-hosted storage. Its Unix server requirement and deleted-file housekeeping warning deserve attention during setup.

Facts from Box Backup's own pages

Backup modes: Backup behavior can be optimized for document or server backup, and traditional snapshot backups are also possible. · github.com, 11 Oct 2026
Backup scope: file · boxbackup.org, 19 Sept 2026
Client platforms: The project lists Linux, Windows, macOS, and other Unix systems as supported client platforms. · github.com, 11 Oct 2026
Components: The system includes a backup store server, a client daemon, and a query and restore tool. · boxbackup.org, 11 Oct 2026
Compression: Files on the server are compressed to reduce storage use. · github.com, 11 Oct 2026
Computer backup: Yes · boxbackup.org, 19 Sept 2026
Connection security: TLS encrypts connections and uses server and client certificates to authenticate both sides. · boxbackup.org, 11 Oct 2026
Encryption: The site says TLS is used to encrypt connections and authenticate servers and clients, while stored file data uses AES and metadata uses Blowfish. · boxbackup.org, 11 Oct 2026
File history: Older file versions and deleted files remain available on the server. · boxbackup.org, 11 Oct 2026
Incremental backups: The client detects file changes, encrypts them, and sends only the changed portions to the server. · github.com, 11 Oct 2026
Incremental transfers: The client sends only changes within files to the server. · boxbackup.org, 11 Oct 2026
Key handling: The site says users must keep a 1k key file safe because server data cannot be decoded without it. · boxbackup.org, 11 Oct 2026
Known limitation: The installation page warns that housekeeping may remove deleted client files quickly and advises alternative backup arrangements for archived files. · github.com, 11 Oct 2026
Platforms: The installation wiki lists packages for Debian, FreeBSD, Windows, Gentoo Linux, Arch Linux, and RPM-based systems, and source compilation instructions for Linux, Mac OS X, FreeBSD, and Windows. · github.com, 11 Oct 2026
Purpose: Box Backup is an open source, automatic online backup system. · boxbackup.org, 11 Oct 2026
Restore modes: file · boxbackup.org, 19 Sept 2026
Restore tool: The software includes bbackupquery, a tool for querying and restoring backups. · boxbackup.org, 11 Oct 2026
Self-hosted storage: Backed-up data is stored as files on a filesystem, and the project says no tape or archive devices are required. · boxbackup.org, 11 Oct 2026
Server backup: Yes · boxbackup.org, 19 Sept 2026
Server setup: The server software runs on a Unix server; the project says Windows is highly not recommended for servers. · github.com, 11 Oct 2026
Support and community: The project invites users to its mailing list for release announcements and discussion. · boxbackup.org, 11 Oct 2026
Support and documentation: The project points users to a user-contributed wiki for documentation and a mailing list for announcements and discussion. · boxbackup.org, 11 Oct 2026
Version history: Old versions and deleted files remain available, with older versions stored as changes from the current version. · github.com, 11 Oct 2026