Kopia

Kopia is an open-source utility for encrypted, snapshot-based backups of selected files and directories. It is best for technically confident individuals, administrators, and small teams that want to choose their own storage and backup policy. The trade-off is that you manage the repository, storage bill, and an unrecoverable password yourself.

Overview

Kopia covers both computer and server file backups, with incremental snapshots and deduplication designed for recurring protection of changing data. Because it does not provide storage, you can place a repository on local or network storage, or use a cloud service you already operate. That flexibility is valuable when infrastructure control matters more than a turnkey subscription.

Its security model encrypts backup data and filenames before they leave the source machine. Ransomware protection, repository consistency checks, and Reed-Solomon error correction address different failure risks, although they do not remove the need to secure the underlying storage account and repository credentials.

Key features

Incremental snapshots and policy controls

Only changed content needs to be captured in later snapshots, while content deduplication avoids storing identical file content repeatedly in one repository. This can reduce repository growth for versioned, frequently changing folders. Policies let you automate schedules, define exclusions, set retention, and apply compression, so you can balance recovery history against storage consumption.

Flexible recovery

You can mount a snapshot as a local disk, restore an entire snapshot to a chosen location, or recover individual files. Mounting is useful for inspecting or retrieving a few items without a full overwrite; complete and selective restores cover both disaster recovery and everyday file recovery.

Encryption and access consequences

Kopia supports AES-256 and ChaCha20 encryption for data and filenames. Every repository uses one password and has no access-control mechanism for sharing. Anyone who receives that password can read the repository, and a forgotten password cannot be recovered. That arrangement suits single-owner repositories but is a significant limitation for organizations needing separate roles or revocation.

Storage and management options

Destinations include Amazon S3 and S3-compatible services, Azure Blob Storage, Backblaze B2, Google Cloud Storage, WebDAV, SFTP, local storage, network storage, and some Rclone providers. Rclone integration is experimental, though Kopia says it has been tested with Dropbox, OneDrive, and Google Drive through Rclone. CLI and GUI interfaces support direct administration, while optional server mode adds an API for centrally managing backups across multiple machines. KopiaUI provides a web interface in server mode; an individual machine normally uses the desktop application.

Pricing

Kopia: free. The software is free and open source, with no software subscription charge. You must provision and pay for the storage destination yourself, so total cost depends on the provider, capacity, retention policy, and transfer requirements. There are no paid Kopia tiers or seat allowances to compare; the practical budget decision is the external repository service and the machines you intend to manage.

This model fits users who already have suitable storage or want to select a provider independently. It is less suitable if you want one predictable bill that includes hosted capacity and vendor-managed storage.

Platforms

CLI and GUI packages support Windows 10 or later, macOS 10.11 or later, and Linux on amd64, armhf, or arm64. The broader platform listing also includes API, self-hosted, and web use through server mode and KopiaUI. Android and iOS are not supported.

Who it's for

Choose Kopia when you need encrypted file backups across computers or servers, want incremental snapshots and granular restores, and are comfortable selecting and paying for storage separately. It is particularly appropriate for self-hosted setups, administrators coordinating several machines through the API, and users who value control over repository placement.

Look elsewhere if nontechnical household users need a provider-managed service, if you require built-in storage, or if shared repositories need individual accounts and revocable permissions. The single, unrecoverable repository password demands disciplined credential management.

Pros and cons

• Pro: Incremental snapshots and deduplication limit repeated storage of unchanged content.
• Pro: Mount, full, and file-level restore modes cover both browsing and major recovery events.
• Pro: Encryption includes filenames, with AES-256 and ChaCha20 options.
• Pro: Broad destination support and server/API operation accommodate self-hosted and multi-machine deployments.
• Con: Storage is not included; provider charges are separate and must be managed by you.
• Con: One repository password provides no per-user sharing controls, and losing it permanently blocks access.
• Con: Rclone support is experimental, so Dropbox, OneDrive, and Google Drive workflows through Rclone carry more uncertainty than the native destinations.

Alternatives

For a hosted service with mobile apps, a free tier, and paid capacity such as 100 GB for one user at $0.25 a month, consider IDrive instead. Jottacloud is another freemium option, including a 5 GB free plan and an unlimited plan at $12.99 a month, for readers who prefer provider-managed storage. Choose rclone when a free, open-source transfer tool across many platforms is the priority rather than Kopia's snapshot and restore system.

Duplicati suits users seeking freemium backup software with a free tier that monitors up to two machines and the last 200 backups. FileCloud is aimed at organizations wanting a managed collaboration and backup platform, with Essentials at $7 a month billed annually and a 20-user minimum. MSP360 Backup offers a free personal workstation tier with file and image-based backup, while restic is a free, fully open-source alternative for Linux, macOS, self-hosted, and Windows. SpiderOak combines open-source software with hosted plans, including a 150 GB option at $6 a month.

For broader comparisons, browse Cloud Backup Services, NAS Backup Software, or Backup software.

Verdict

Kopia is a strong choice for users who want encrypted, policy-driven snapshots, several restore paths, and freedom to choose storage across computers and servers. Choose it when repository control and open-source operation outweigh setup and credential responsibilities. Look elsewhere for included storage, mobile coverage, managed accounts, or a password-recovery path.