# kopia/kopia

Cross-platform backup tool for Windows, macOS & Linux with fast, incremental backups, client-side end-to-end encryption, compression and data deduplication. CLI and GUI included.

Repository: https://github.com/kopia/kopia
Canonical: https://ross.abutalabs.com/products/kopia
Homepage: https://kopia.io
Language: Go
License: Apache-2.0
License Family: permissive
Topics: deduplication, backup, google-cloud-storage, encryption, cloud
Last push: 2026-08-25T00:36:24+00:00

## Health v2 (maintenance only)
Score: 96/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 99, release rhythm 89, longevity 100
- inputs: {"age_days": 3910, "days_push": 9, "days_rel": 79, "gap_med": 7, "n_releases_24m": 14}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 13968, forks 712 (observed 2026-08-28T04:11:05.214485+00:00)

## What it is
Kopia is a fast, open-source backup and restore tool that creates encrypted, compressed, and deduplicated snapshots of files and directories, storing them in cloud, network, or local repositories. It offers both a CLI and a GUI (KopiaUI), with client-side end-to-end encryption and an optional server mode for centrally managing backups of multiple machines.

## Use cases
- back up my files to cloud storage with end-to-end encryption
- create incremental snapshots of directories with deduplication
- restore files from a point-in-time backup snapshot
- back up a laptop or server to S3, B2, Azure, or Google Cloud Storage
- centrally manage backups of multiple machines from a server
- encrypt backups locally before uploading to untrusted storage

## When to choose
- you need encrypted, deduplicated, incremental file-level backups across Windows, macOS, and Linux
- you want both a CLI for scripting and a GUI for regular users
- you want to back up to a wide range of cloud providers (S3, B2, Azure, GCS, SFTP, WebDAV, Rclone)
- you need a server mode to manage backups of many machines centrally

## When to avoid
- you need full disk-image or bare-metal recovery backups
- you want a simple unencrypted backup without repository/policy concepts
- you need block-level or database-aware hot backups

## Facets
- artifact type: application
- maturity: stable
- function: backup, cryptography, compression, cli, gui, self-hosted
- domain: files, security, cloud-computing, privacy, cross-platform
- platform: windows, cross-platform, cli, self-hosted
- tags: backup-tool, deduplication, end-to-end-encryption, snapshots, cloud-storage, restore, incremental-backup, macos, linux, docker

## Member repositories
- kopia/kopia (main) score 96

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:11:05.214485+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-29T17:12:54.694205+00:00, confidence not recorded.
  - readme: https://github.com/kopia/kopia (fetched 2026-08-28T04:11:05.214485+00:00, sha 5f9cfd3a5e31)
  - homepage: https://kopia.io (fetched 2026-08-29T08:06:57.598686+00:00, sha 6b02d6e4e407)
  - site_page: https://kopia.io/docs/features (fetched 2026-08-29T08:06:57.601726+00:00, sha 010a1e0688b5)
  - site_page: https://kopia.io/docs/getting-started (fetched 2026-08-29T08:06:57.604070+00:00, sha 0ac87a7abaee)
  - site_page: https://kopia.io/docs/installation (fetched 2026-08-29T08:06:57.606860+00:00, sha a4db448f9356)
  - site_page: https://kopia.io/docs (fetched 2026-08-29T08:06:57.608990+00:00, sha 9dfed921c4e1)
  - site_page: https://kopia.io/docs/privacy-policy (fetched 2026-08-29T08:06:57.610811+00:00, sha 824cd2479c03)
- Data as of 2026-08-30T08:39:29.467469+00:00.