Duplicati: when to install it, and when not to
Duplicati is a free, open-source backup tool that encrypts and de-duplicates your data before sending it to local drives, NAS or cloud storage, with…
The short version
Duplicati: Scheduled encrypted incremental backups to a local drive, a NAS or cloud storage, with a browser interface and retention rules. Good for a home setup. Test a restore before you trust it with anything.
| Licence / price | Free · Open source |
|---|---|
| Platforms | Windows, macOS, Linux |
| Category | Backup & Sync — 5 programs |
| Official download | https://duplicati.com/download ↗ |
What it is for
Duplicati is a free, open-source backup tool that encrypts and de-duplicates your data before sending it to local drives, NAS or cloud storage, with scheduled and versioned backups. For a proper off-site, encrypted history of your files, it is a strong free pick.
When to pick something else
The interface is less friendly than commercial backup apps, and a misconfigured schedule or destination means you discover gaps only when you need the backup. Restore must be tested, because an untested backup is a hope, not a safety net.
How it compares in Backup & Sync
These are the alternatives we would consider for the same job. The notes are the same ones used on the main list, so there is no separate ranking hiding on this page.
| Program | Licence / price | Platforms | Why it is on the list |
|---|---|---|---|
| Syncthing Publisher's site ↗ | Free · Open source | Windows, macOS, Linux, Android | Keeps folders identical across your own devices, peer to peer, with no cloud in the middle and no account. Because deletions propagate, it is synchronisation rather than backup. Pair it with versioning turned on. |
| FreeFileSync Publisher's site ↗ | Free · Open source | Windows, macOS, Linux | Compares two folders and shows you exactly what will be copied, moved or deleted before anything happens, then does it and verifies the result. The clearest free tool for mirroring to an external drive. |
| Restic Publisher's site ↗ | Free · Open source | Windows, macOS, Linux | A single command line binary that does fast, encrypted, deduplicated snapshots to almost any storage backend. The choice for people who want backups they can script and verify rather than click through. |
| Backblaze Personal Backup Publisher's site ↗ | Paid · From $99/year | Windows, macOS | Unlimited cloud backup of one computer for a flat annual fee, including external drives. The one paid subscription on this page that most households should genuinely consider, because off-site is the part people skip. Free 15-minute restore window for the first 30 days. |
Practical notes
- Set a schedule and actually run a test restore once.
- Keep the encryption passphrase in your password manager.
- Use de-duplication to shrink repeated backups.
Questions people ask
Is Duplicati open source?
Yes, and it targets many back-end storages.
Is my backup encrypted?
By default it encrypts before upload, so the storage provider sees only ciphertext.
Free tier limits?
The software is free; you pay only for the storage you choose.
Where it appears in our guides
- Setting up a new Windows PC: the order that actually works
- Before and after a clean reinstall: the checklist
- Building a reliable remote-work machine
- A backup you can actually restore
- Do you need a third-party antivirus on Windows 11?
See the full Backup & Sync explainer for the other 4 programs in this category.
How to read this page. How to read this page. Platform, licence and publisher details come from our directory data. Where an independent review, audit or survey is mentioned, it is summarised in our own words with the source named and linked; our /sources page sets out that policy. The recommendation, the trade-offs and every 'skip it if' line are our editorial judgement. We do not run benchmarks, publish measured performance figures or host installers, and every download link goes to the publisher's own site. If a detail is out of date, our About page explains how to tell us.