Kopia is a free, open-source backup tool with end-to-end encryption and deduplication. Compare its features, repository options and top alternatives.
Kopia is a free, open-source backup and restore tool created and led by Google engineer Jarek Kowalski, designed to create encrypted, deduplicated snapshots of files and directories and store them in a repository of the user's choosing. Because it is a community open-source project rather than a company, it has no pricing, funding or headquarters — the software itself is entirely free to use.
The project receives ongoing engineering support from Kasten by Veeam, the Kubernetes-native backup division Veeam acquired in 2020, which uses Kopia internally for Kubernetes backup workflows and contributes to its continued development. This gives Kopia a level of sustained corporate investment that is unusual among community-maintained open-source backup tools.
Kopia's defining feature is that it never creates unencrypted backups: every snapshot is encrypted client-side with user-controlled keys before leaving the device, protecting both file contents and file/directory names. Alongside encryption, Kopia performs content-based deduplication so identical data is stored only once across a repository, plus compression and error correction to minimize storage costs and guard against corruption.
Repository backends include Amazon S3 and S3-compatible storage, Azure Blob Storage, Backblaze B2, Google Cloud Storage, WebDAV/SFTP-accessible servers, and local or network-attached storage. Kopia ships with both a command-line interface for automation and scripting and a graphical desktop app (KopiaUI) for visual configuration, snapshot review and restores, with native support on Windows, macOS and Linux.
Kopia itself is completely free and open source, with no license fees, subscriptions or paid tiers of any kind. The only cost users incur is for whichever storage backend they choose to pair with Kopia, such as Amazon S3, Backblaze B2 or Azure Blob Storage fees, which are billed directly by those providers rather than by the Kopia project.
This makes Kopia's total cost of ownership entirely a function of the storage a user selects and how much data they back up, rather than any fee tied to the backup software itself, distinguishing it from commercial backup services that charge per-device or per-user subscription fees on top of storage costs.
Yes, Kopia is completely free and open source with no license fees or paid tiers; users only pay for their chosen storage backend.
Yes, Kopia encrypts all data client-side with user-controlled keys before it leaves the device, and does not support creating unencrypted backups.
Kopia supports Amazon S3 and S3-compatible services, Azure Blob Storage, Backblaze B2, Google Cloud Storage, WebDAV/SFTP servers, and local or network-attached storage.
Yes, Kopia includes both a command-line interface and a native graphical desktop app called KopiaUI, available on Windows, macOS and Linux.
Kopia is led by Google engineer Jarek Kowalski and receives ongoing development support from Kasten by Veeam, which uses Kopia for Kubernetes backup workflows.
Yes, Kopia performs content-based deduplication so identical file content is stored only once across a repository, even when shared across multiple machines.