Comparison

Duplicati vs Kopia

Duplicati lands on Depends, and Kopia lands on Worth it.

Duplicati

Depends

Confidence: Medium

Buy it if you're technical and want free, encrypted backups to your own cloud storage.

Worth it

Confidence: Medium

Free, fast, encrypted open-source backup that technical users and self-hosters love.

Duplicati versus Kopia
Compare	Duplicati	Kopia
Verdict	Depends	Worth it
Best for	Homelab and self-hosting users	Self-hosters and NAS owners
Who it's not for	Businesses needing vendor SLAs or support contracts	Non-technical users wanting set-and-forget backups . use Backblaze or Time Machine
Privacy	Client-side AES-256 encryption by design, but 2026 CVEs (privilege escalation, permission issues) require prompt patching.¹¹	Encrypted by default; one critical server RCE (CVE-2026-45695) fixed in 0.23.0 . run the latest version.
Support quality	Community forum only; no vendor SLA	Community forums only; no paid support
Public sentiment	Users praise the free, powerful encrypted backups while repeatedly complaining about reliability and trust issues.^⁹	Overwhelmingly positive among self-hosters and technical users who praise its speed, with a minority reporting defaults and performance issues.
Biggest gotcha	Restores matter most; Reddit reports of failures mean you must test restores regularly^⁸	Patch to 0.23.0+ before running Kopia server; unauthenticated RCE (CVE-2026-45695)

Non-technical users wanting set-and-forget backups . use Backblaze or Time Machine
Businesses needing vendor SLAs and support contracts
Anyone who won't promptly patch an internet-exposed Kopia server
Guess: enterprises needing certified compliance and managed backup