The drawings folder lives on the office PC. A copy lives on the site manager's laptop. A third copy went to the yard on a memory stick last Tuesday. Nobody is certain which one is current, and the argument about it costs more than the job. Syncthing solves exactly this and nothing else: it keeps chosen folders identical across your machines, with no cloud account in the middle.
What Syncthing actually is
You pick a folder and the machines you want it on. Syncthing keeps them the same. Change a file on the office PC and it appears on the laptop; delete it there and it goes here. The devices talk to each other directly and encrypted — the files never sit on anybody's server, including ours.
It is free and open source. There is no per-user fee, no storage tier and no account to sign up for. The pairing is done once with a device key, and after that it simply runs.
Where it earns its keep
The flash drive disappears. Folders that used to travel by USB stick — drawings, photos from site, scans, exports — arrive by themselves, usually before the person does.
It works where the internet does not. Two machines on the same site network sync at full local speed even if the line to the outside world is down. For a workshop, a yard or a van with a laptop in it, this matters more than any cloud feature.
Nothing goes through a third party. For drawings under NDA, photographs of clients' property or anything a customer has asked you to keep off the cloud, this is a straight answer rather than a paragraph of reassurance.
Big files stop being a problem. Video from site visits, CAD, photo libraries — no upload limits and no monthly bill that grows with the folder.
What it is not, and this matters
Syncthing is not a backup. This is the mistake we see most. If a file is deleted or encrypted by ransomware on one machine, the deletion syncs everywhere within seconds. It keeps a short history of changed versions if you set that up, but a proper backup is a separate thing that lives somewhere the sync cannot reach.
It is not for editing one document together. Two people editing the same spreadsheet at once will produce a conflict file, not a merged result. If that is your workflow, you want Nextcloud or Microsoft 365, not this.
It is not remote access. Syncthing copies folders; it does not let you reach the office machine. That is a different job — see our note on remote access without a VPN server.
When it fits, in plain terms
It fits when a handful of people need the same set of files in more than one place, each mostly works on their own files, and the folder is too big or too sensitive to sit in a cloud subscription. Builders with drawings, photographers with shoots, workshops with machine files, anyone moving large exports between an office and a second site.
It does not fit when you want links to send clients, shared calendars, or access from a phone in the street. That is a file server's job.
What it costs with us
Setting it up is £120 one-off: the folders and machines you name, the direction of sync — some folders should only travel one way — file version history so a bad overwrite can be undone, and a check that it survives a reboot. We also tell you honestly where the gaps are, which usually means adding a real backup.
Syncthing itself is free and stays free. If the machines are in different places and cannot see each other, they need a way to meet — usually the private network described in the Tailscale piece above. And if you decide a proper file server is the better answer after all, the Managed VPS page has the sizes and prices.
Not sure which of the three you need? That is what the free IT health check is for: we look at how your files actually move today and tell you which of these is worth doing, including the answer "none of them, fix this instead".
Related
When your own file server makes sense · Remote access without a VPN server