Restic vs Duplicacy
two backup philosophies, one license you should know about

Quick summary

• Choose Restic if:You want fully open-source with no usage restrictions, you're backing up commercial workloads, or you value the larger ecosystem of clients, hosts, and tooling.
• Choose Duplicacy if:You're a personal user backing up a single machine, you want lock-free concurrent backups from many clients to one repo, or you specifically want the GUI experience.

The licensing thing nobody mentions upfront

This is the part most "Restic vs Duplicacy" articles skip, and it's the most consequential difference for a lot of people:

• Restic license:BSD 2-Clause. Use it on as many machines as you want, personal or commercial, no fees, no registration.
• Duplicacy CLI:Free for personal use only. Commercial use requires a paid license — currently $25/year per computer.
• Duplicacy Web/GUI:Paid for everyone — personal and commercial. Trial available.

If you're a homelabber backing up one personal NAS, Duplicacy CLI is free and fine. The moment you back up a work laptop or a small business server, you're in commercial-license territory. This is fully legitimate — Duplicacy's author has put years into the project and deserves to charge for it. But you should know before committing.

Side-by-side comparison

Feature	Restic	Duplicacy
License	BSD 2-Clause (fully open-source)	Dual license: free personal CLI, paid commercial CLI, paid GUI
Cost — personal	Free	Free (CLI), paid (GUI)
Cost — commercial	Free	$25/year per computer (CLI)
Source available	Fully open	Source-available, not OSI open-source
Platforms	Linux, macOS, Windows, FreeBSD, OpenBSD	Linux, macOS, Windows, FreeBSD
Deduplication	Content-defined chunking (CDC), variable-size	Lock-free CDC, designed for many-clients-one-repo
Concurrent clients	Supported, requires careful coordination	Lock-free design, easier multi-client repos
Encryption	AES-256-CTR + Poly1305 MAC	AES-256-CFB
Compression	zstd (default since 0.14)	zstd, lz4
Backends	S3, B2, Azure, GCS, SFTP, REST, local, rclone	S3, B2, Azure, GCS, Wasabi, SFTP, WebDAV, local, OneDrive, Google Drive
GUI	None official (third-party: Backrest)	Official paid Web GUI
Mature ecosystem	Large — many hosts, clients, tutorials	Smaller, more centralized around official tools
Hosted providers	Many: ServerCrate, BorgBase (via SFTP), rsync.net, Backblaze, Wasabi	Generic object storage; few Duplicacy-specific hosts

Where Duplicacy genuinely wins

• Multi-client backups to one repo.Duplicacy's lock-free design lets multiple machines back up to the same repository concurrently without locking issues. Restic can do this but with more care required.
• The official GUI.If you want a polished, supported web UI out of the box without bolting on Backrest, Duplicacy Web is more turnkey.
• More cloud storage backends out of the box.Including consumer-friendly ones like OneDrive and Google Drive — useful if you want to use existing storage you already pay for.

Where Restic wins

• Licensing simplicity.Free for everything, forever, no per-machine fees, no commercial-use audit risk.
• Ecosystem size.More hosted providers, more client tools, more tutorials, more community knowledge on Stack Overflow and forums.
• Cross-platform parity.Restic's Windows support is excellent. Duplicacy works on Windows but the GUI experience is more polished on Restic via Backrest these days.
• Fully OSI open-source.If your org has policies requiring OSI-approved licenses, Duplicacy's source-available license may not qualify. Restic's BSD 2-Clause does.

Migrating from Duplicacy to Restic (or vice versa)

The repository formats are completely incompatible. There is no automated migration path. If you want to switch:

1. Keep your old tool's repo accessible for the length of your retention window (typically 90 days to 1 year)
2. Set up the new tool with a fresh repository on the same or different storage
3. Run both in parallel until you're confident the new one is reliable
4. Once the old retention window expires, decommission the old repo

This is annoying but standard for backup tool migrations. Don't try to do an instant switch — you'll lose history.

Hosting both: storage backend considerations

If you want a managed SFTP backend that works with either tool, you have options. Restic-first hosts (ServerCrate, BorgBase via SFTP, rsync.net) all support Duplicacy as well, since SFTP is just SFTP. The repo format is up to your client — the host doesn't care.

Practical note: Duplicacy hosting providers specifically (as in, "Duplicacy-aware") barely exist. The author maintains a Storj-based service but it's narrow. For most users, "host that supports SFTP and Restic" is also "host that supports Duplicacy."

FAQ

Is Duplicacy actually open-source?

Source-available, not OSI open-source. The code is published on GitHub but the license restricts commercial use and GUI distribution. This is a meaningful distinction for organizations with open-source policies, even if it makes no difference to a homelabber.

Which is better for a homelab with one machine?

Personal preference. Duplicacy CLI is free and the lock-free design is a nice property. Restic's broader ecosystem means more tutorials and more hosted backends to choose from. Both work well. Pick one and stop comparison-shopping.

Which is better for a small business?

Restic, almost always. Free license, no per-machine accounting, larger ecosystem. The cost difference adds up fast at 10+ machines and you avoid licensing audit complexity entirely.

Does ServerCrate work with Duplicacy?

Yes — ServerCrate is SFTP-based and Duplicacy supports SFTP. Our tooling and docs are Restic-first, but if you point Duplicacy at our endpoint with your credentials, it works. The repo format on disk will be Duplicacy's, not Restic's, and you can't switch later without re-backing-up.

Is the lock-free dedup actually a big deal?

For one machine? No. For 50 laptops backing up to one company repo? It's a real advantage. Most homelab and small-team users will never hit a workload where this matters.