Transfer passwords
TransferSize protects each password with PBKDF2-SHA-256, a random salt, and 210,000 rounds of processing. The password locks the transfer page. It does not encrypt the file in your browser before upload.
Private chat
Chat uses HTTPS or WSS while messages travel. Messages are encrypted again before they are stored. This is not end-to-end encryption because TransferSize must be able to read a message to deliver it or review a copy that someone reports.
Upload checks
Large uploads are split into parts. TransferSize checks those parts and can retry a failed one without starting over. This lowers the chance of a broken upload, but it does not replace your own backup.
Account and app passwords
A public download page does not give someone access to your account. WebDAV uses a separate app password that you can cancel at any time. The password is shown once and is not stored in plain text.
What you should do
Check who will receive the link. Send the password in a different message. Use a short expiry, remove links and app passwords you no longer need, keep the original file, and report anything suspicious to support@transfersize.com.
Questions people ask
Is TransferSize end-to-end encrypted?
No. Secure connections protect data while it travels, and chat messages are encrypted before storage. TransferSize can still read chat messages when needed to deliver them or review a safety report.
Can I take back a downloaded file?
You can close the link to stop future downloads. You cannot remove a copy that someone already downloaded.
How do I report a security problem?
Email support@transfersize.com with clear steps that show the problem. Do not open or keep data that is not yours.