A secure WeTransfer alternative with zero-knowledge encryption
What zero-knowledge changes for everyday file transfer, how a protected link actually works, and the trade-offs nobody mentions on the pricing page.
Try it in one click.
Three private surfaces. Same zero-knowledge architecture.
Same workflow, different foundation The workflow people want is unchanged: drop a file, get a link, send it, done. Zero-knowledge does not change any of that. It changes what exists on the server while the link is alive.
What happens when you drop the file in - A fresh symmetric key is generated on your device. - The file is encrypted locally with XChaCha20-Poly1305, an authenticated cipher, so tampering is detected rather than silently accepted. - Ciphertext uploads in chunks. The server stores an opaque blob it has no key for. - The link you copy contains key material in its URL fragment — the part after the # that browsers never send to a server. - A passphrase, derived through Argon2id, gates the open.
The recipient's browser downloads ciphertext and decrypts it locally. At no point does a readable copy exist on our side.
Why the passphrase is not just a password field On a conventional transfer service, a download password is an access check performed by a server that already holds your readable file. Turn off the check and the file is still there, readable.
In a zero-knowledge system the passphrase participates in deriving key material. Without it there is nothing to serve — not to an attacker, not to an employee, not to us.
That is also why you should send the link and the passphrase on different channels: link by email, passphrase by phone or SMS. Compromising one channel then yields nothing useful.
Expiry as a safety property Public links here expire within 24 hours at most. That is shorter than most transfer services, on purpose.
Long-lived links accumulate. They get forwarded, pasted into group chats, indexed from a document, and rediscovered years later by someone the file was never meant for. A short ceiling means an old link is an expired link. If someone needs ongoing access, the correct answer is membership of an encrypted space with their own key — not a link that lives forever.
The trade-offs, stated plainly - **No password reset that recovers your data.** We hold no key. Recovery depends on an offline Recovery Kit you print and store. - **No provider-side preview of everything.** Previews happen on your device. - **No content scanning.** We cannot scan what we cannot read; recipients keep their normal endpoint protection.
These are consequences of the guarantee, not omissions. Any service offering both real zero-knowledge encryption and a support-desk data recovery is describing something that cannot both be true.
Who this suits Freelancers sending client deliverables under NDA, studios moving unreleased material, professionals handling legal, financial or medical documents, and anyone who would rather the transfer service be structurally incapable of reading their work.
Try it in one click.
Three private surfaces. Same zero-knowledge architecture.