Duplicacy — cross-platform backups with deduplication that works everywhere
Duplicacy is a backup tool that focuses on making deduplication work across multiple machines and storage locations. It’s available for Windows, macOS, and Linux, and can run either as a command-line tool or with a GUI client.
The main selling point: all backups, no matter which machine they come from, can share the same storage and still deduplicate against each other. That means less space used if you’ve got similar data across systems — useful for corporate fleets or dev teams with shared codebases.
It supports a wide range of destinations: local disks, NAS shares, SFTP, cloud buckets (AWS, Backblaze B2, Google Cloud, Azure), and more. Client-side encryption is built in, so untrusted storage locations aren’t a problem.
Capabilities
| Feature | Description |
| Cross-Platform | Windows, macOS, Linux |
| Global Deduplication | Identical data across different machines is stored once |
| Destinations | Local, NAS, SFTP, and multiple cloud providers |
| Encryption | Client-side, protects data before it leaves your system |
| Scheduling | Automated backups via built-in scheduler or system tools |
| Pruning | Configurable retention for old snapshots |
| Compression | Reduces storage usage alongside deduplication |
| Restore Options | Restore whole backups or single files/folders |
Deployment Notes
– One storage repository can serve many clients — plan naming conventions early.
– Encryption keys must be stored safely; losing them means losing access to the data.
– Command-line version is lighter and more scriptable; GUI is better for end users.
– Deduplication savings are best when multiple machines have similar data sets.
– First backup is always full; after that, only new or changed data is sent.
Quick Start (Example for Linux CLI)
# Initialize storage
duplicacy init mybackup sftp://user@host/path
# Back up a directory
duplicacy backup
# List backups
duplicacy list
# Restore files
duplicacy restore -r
Where it’s useful
– Backing up multiple similar systems to the same cloud bucket.
– Small teams sharing large codebases or datasets.
– Mixed-OS environments needing a single backup tool.
– Offsite encrypted backups to public cloud without trust issues.
– Situations where storage efficiency matters as much as reliability.