Where do my files go?
From your device straight to the recipient's device. StrongFolder does not upload your files to a cloud and does not keep a copy. The service's servers help the two browsers find each other and, when needed, relay the encrypted stream — they do not store file contents.
How is a transfer protected?
| Stage | What happens | Protection |
|---|---|---|
| Creating the link | Your browser registers the session: names, sizes, file count | HTTPS to strongfolder.com |
| Connecting | A signalling service introduces the two browsers | HTTPS / secure WebSocket |
| Transfer (direct) | Data flows browser to browser | WebRTC data channel, DTLS encryption |
| Transfer (relayed) | A StrongFolder TURN server forwards the stream | The stream stays DTLS-encrypted between the two browsers; the relay forwards it and does not store it |
| After the transfer | You stop sharing or close the tab | The link no longer serves files |
What does "not stored" mean exactly?
The content of your files never sits on a StrongFolder server — not for a minute, not for seven days. Compare that with transfer services that keep an uploaded copy for days or weeks. What we do keep is the information needed to show the link page: file and folder names, sizes and the number of files. If you choose to sign in with Google, your e-mail is kept so you can see your transfers.
Is a peer-to-peer transfer safe?
"Peer-to-peer" here means your browser talks to one recipient's browser — it is not a public file-sharing network like BitTorrent, and your files are not offered to strangers. The recipient needs your link. The risks to manage are the usual ones for any link:
- Share the link privately — in a direct chat or e-mail, not in a public post.
- Check who is downloading — StrongFolder shows how many users are connected.
- Stop sharing when the recipient has the files.
- Keep your browser updated — WebRTC security comes from the browser.
Does my IP address become visible?
For a direct connection, the two browsers exchange network addresses, as in any video call. If you don't want the recipient to see your IP address, use a VPN; the transfer will then run through the VPN or our relay.
Read more
- Secure file sharing: a practical guide
- How WebRTC file transfer works
- Privacy Policy · Cookie Policy
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