Security & privacy
The short version: your files go device to device. Our server introduces the two browsers and holds no files — not even for a second.
What our server sees
| Data | Does the server see it? |
|---|---|
| File contents | Never. The server refuses binary data outright and has no code path that stores or forwards file bytes. |
| File names, types, sizes, the file list | No. These travel only over the encrypted connection between the two browsers. |
| Room ID and 6-character code | Yes — it creates them. They live in memory and are deleted when the sender leaves or after 24 hours. |
| WebRTC connection details (SDP, ICE candidates) | Yes, in passing. These describe how to reach each browser — IP addresses, ports and certificate fingerprints. The server forwards them to the other side and keeps no copy. |
| Your IP address | Yes, as any website does. It is used in memory to rate-limit abuse and appears in standard web server access logs, which are kept for a short period for security and traffic statistics. |
We do not run analytics scripts, advertising trackers or third-party fonts on wetransfertool.com, and the pages set a strict Content Security Policy and send no referrer to other sites, so a room link cannot leak through a click.
How transfers are protected
- Encryption in transit. WebRTC data channels are always encrypted with DTLS. There is no unencrypted mode.
- Security check. Both screens show five symbols derived from both sides’ DTLS certificate fingerprints. Matching symbols mean the connection was not intercepted — even by someone who could tamper with our server.
- Integrity. Every file gets a SHA-256 checksum on both ends; a mismatch is shown clearly.
- Hard-to-guess links. Room IDs are 128 random bits. Codes are shorter, so guessing them is rate-limited per network and they only work while the sender’s tab is open.
- No relay. If a direct connection cannot be made, the transfer does not start. We would rather tell you than route your files through our hardware.
What this does not protect against
We would rather be clear about the limits than oversell:
- Anyone with the link or code can ask for the files while your tab is open. Share it only with the person you mean, and check the security symbols with them.
- Your IP address is visible to the other person’s browser, as it is in any direct connection, and the two IP addresses pass through our server during setup.
- A compromised device on either end can read the files, as with any transfer method.
- Downloads are not scanned. We never have the files, so we cannot check them for malware. Only open files from people you trust.
Reporting a problem
Found a security issue or misuse of BeamDrop? Email hello@wetransfertool.com. Because files never pass through us, we cannot inspect or take down content, but we can block abusive traffic and fix vulnerabilities. See the privacy policy and terms for the formal version.