How to Sync Files Between Computers Without the Cloud

Why sync without the cloud?

Cloud file sync services like Dropbox, Google Drive, and OneDrive are convenient, but they come with trade-offs:

• Privacy. Your files are stored on someone else's server. Even with encryption, the provider has access to metadata, file names, and sharing patterns.
• Speed. Sync speeds are limited by your internet connection. Large files or folders with many small files can take hours.
• Cost. Cloud storage subscriptions add up to $10–15 per month per user, or more for business plans.
• Internet dependency. No internet means no sync. Some providers offer offline access, but changes don't sync until you're back online.
• Account management. Signing in, managing shared folders, and dealing with sync conflicts all add friction.

For many users, the solution is simpler: keep files on your own network. Here are four ways to do it.

LAN file sync: automatic, real-time, private

LAN sync tools transfer files directly between your devices over your home network. There's no cloud server, no internet dependency, and no ongoing cost.

CoveSync

CoveSync is a dedicated LAN sync tool designed for simplicity. Pair devices with a 6-digit PIN, share a folder in two clicks, and files sync automatically whenever devices are on the same network. Firewall rules are configured automatically on Windows, macOS, and Linux.

• Free on Linux, $27 one-time for Windows and macOS (no subscription)
• Mutual TLS encryption for all transfers
• Clipboard sharing between devices
• Web UI with folder browser and sync history
• Android companion app (coming soon)

Syncthing

Syncthing is a free, open-source sync tool that supports both LAN and internet sync. It has more advanced features like file versioning and untrusted devices, but setup is more involved. You'll need to exchange device IDs, configure firewall rules manually, and edit configuration files to share folders.

• Completely free and open source
• Supports internet sync via global discovery and relay servers
• Full Android peer app (syncs directly device-to-device)
• Steeper learning curve

Resilio Sync

Resilio Sync (formerly BitTorrent Sync) uses peer-to-peer technology for cloud-free sync. It offers both LAN and internet sync with encrypted transfers. The free version now includes all features previously reserved for the paid Pro plan.

• Free with registration (no subscription)
• Supports internet sync
• Requires account registration

USB drives and external storage

The simplest approach: copy files to a USB drive, plug it into the other computer, and copy them off. It's manual, but it works everywhere and costs nothing if you already have a drive.

Pros: Simple, works offline, no software to install, no privacy concerns.

Cons: Manual process, easy to forget, no automatic sync, risk of losing the drive, not practical for frequent syncs or large numbers of files.

Best for: Occasional transfers, one-time migrations, or when you don't need ongoing sync.

Self-hosted cloud (Nextcloud, ownCloud)

Self-hosted platforms like Nextcloud give you a cloud experience (web access, mobile apps, file sharing), but you control the server. You can run it on a spare PC, a VPS, or a NAS.

Pros: Full cloud feature set (file sharing, calendars, contacts, apps), accessible from anywhere, you control the data.

Cons: Requires a server (always-on machine or VPS), significant setup and maintenance, still uses internet bandwidth for off-network access, potential security risks if not configured properly.

Best for: Users who want a full cloud experience without third-party servers, have technical skills to maintain a server, and need access from outside their home network.

Network-attached storage (NAS)

A NAS is a dedicated storage device on your network. Devices access files directly from the NAS rather than syncing copies. Many NAS devices run Linux and can also run sync tools like CoveSync or Syncthing.

Pros: Centralized storage accessible to all devices, usually supports RAID for redundancy, can run additional services (media server, backups).

Cons: Requires hardware purchase ($150+), not true sync (changes aren't automatically mirrored across devices), single point of failure without RAID, generally slower than direct device-to-device sync.

Best for: Homes or offices with multiple users who need shared access to the same files, or as a central backup target.

Which method is right for you?

Set up LAN sync in five minutes

Here's how to get started with CoveSync, the easiest way to sync files over your local network:

That's it. From now on, whenever both devices are on the same network, CoveSync keeps them in sync automatically. No accounts, no subscriptions, no cloud.

Frequently asked questions