Kopia

Kopia is open-source backup software that turns selected files and directories into encrypted snapshots in storage you choose. It is best for technically confident individuals and teams that want policy-level control over repositories, schedules, and retention. The trade-off is operational responsibility: you supply the storage, protect a single repository password, and manage access yourself.

Overview

Kopia covers computer and server backup, with file-based scope and mixed restore modes. Incremental snapshots and content deduplication keep repeated file content from being stored more than once, making it well suited to ongoing protection of changing data rather than occasional one-off copies.

It does not provide storage. You must provision and pay the selected local, network, or cloud destination, so total backup cost depends on that provider and your retained data. This arrangement suits users who already have an S3-compatible account, NAS, or other repository location; readers seeking an all-inclusive hosted backup service should look elsewhere.

Key features

Policies and recovery

Policies can automate snapshot schedules, exclude paths, define retention, and apply compression. That gives administrators useful control over backup volume and lifecycle without manually managing every run. Recovery is similarly flexible: mount a snapshot as a local disk, restore everything to a chosen location, or retrieve individual files. Selective restore is particularly useful when a whole-system rollback would be excessive.

Encryption and integrity

Kopia encrypts backup data and filenames before they leave the machine, supporting AES-256 and ChaCha20. Reed-Solomon error correction and repository consistency checks add protection against corruption, while ransomware protection strengthens its role as a defensive backup layer.

Security depends heavily on credential discipline. Each repository has one password and no access-control mechanism for sharing; anyone who receives it can access the data. Kopia cannot recover a forgotten password, so losing it can make the repository unreadable. This model is unsuitable where different users need separate permissions.

Storage and interfaces

Destinations include Amazon S3 and compatible services, Azure Blob Storage, Backblaze B2, Google Cloud Storage, WebDAV, SFTP, local and network storage, plus some Rclone providers. Rclone integration is experimental, although Kopia says Dropbox, OneDrive, and Google Drive have been tested through it; treat that route as a less dependable choice than its direct integrations.

A command-line interface and desktop GUI cover individual machines. Optional server mode exposes an API for centrally managing backups across multiple computers, and KopiaUI supplies a browser interface in that mode. Desktop packages support Windows 10 or later, macOS 10.11 or later, and Linux amd64, armhf, or arm64.

Pricing

There are no software subscription charges or seat and quota tiers. The meaningful expense is the storage service you connect, and its capacity and billing terms determine the ongoing cost. Kopia therefore fits users comfortable assembling their own backup stack, not readers who want one predictable fee that includes hosted capacity and support.

Platforms

Kopia offers API, Linux, macOS, self-hosted, web, and Windows options. CLI and GUI packages support Windows 10+, macOS 10.11+, and Linux on amd64, armhf, or arm64. The web interface is provided by KopiaUI when server mode is running; a single computer normally uses the desktop application.

Who it's for

Choose Kopia if you need encrypted, incremental file snapshots across computers or servers and want to decide exactly where repositories live. Its scheduling, retention, deduplication, and restore choices reward users willing to manage storage and credentials. It is a weaker fit for nontechnical households, teams requiring per-user repository permissions, or anyone unwilling to accept irreversible password loss and separate storage billing.

Pros and cons

• Pros: Incremental snapshots and deduplication reduce repeated repository content.
• Pros: Encryption covers filenames as well as data before transfer, with AES-256 and ChaCha20 options.
• Pros: Mount, full, and file-level restores accommodate different recovery jobs.
• Pros: Scheduling, exclusions, retention, compression, integrity checks, and error correction provide substantial policy control.
• Cons: Storage is not included; you pay and administer the provider yourself.
• Cons: One repository password and no sharing access controls make delegated access impractical.
• Cons: A forgotten repository password cannot be recovered.
• Cons: Rclone support is experimental.

Alternatives

Cloud Backup Services are the better starting point when you want to compare hosted options rather than provision storage yourself. For storage already on a NAS, see NAS Backup Software; for a broader category survey, see Backup software.

• IDrive suits readers wanting freemium hosted plans, mobile apps, and a free trial, with a 100 GB Mini plan at $0.25 a month for one user.
• Jottacloud is a hosted freemium alternative with a 5 GB free tier and an Unlimited plan at $12.99 a month.
• rclone is a free open-source option for connecting storage services directly, rather than providing Kopia's snapshot system.
• Bareos offers a free open-source community edition for readers seeking a different backup platform.
• Duplicati provides a free tier monitoring up to two machines and 200 backups, plus a paid Pro plan.
• MSP360 Backup offers personal workstation file and image backup, with forum-based support on its free plan.
• SpiderOak combines open-source software with hosted plans, including 150 GB at $6 a month.
• Knoxite is another free, open-source, self-hosted data storage and backup system.

Verdict

Kopia is a strong choice for technically capable users who want encrypted, deduplicated snapshots and granular control over storage and retention. Choose it for that control and its capable recovery paths; look elsewhere if you want included storage, recoverable credentials, or fine-grained sharing permissions.