What file sizes are supported?

Free plan supports files up to 10MB. API Starter and API Pro plans support up to 10MB. API Business plan supports files up to 30MB.

How are files encrypted?

Files are encrypted using AES-256-GCM in your browser before upload. The encryption key never leaves your device. We only ever store encrypted ciphertext.

What types of files can I send?

You can send any file type including documents, images, archives, and more. There are no restrictions on file types, only on file size based on your plan.

What happens to the file after it is downloaded?

After the first read/download, the encrypted file is permanently deleted from our servers. We generate a signed ECDSA deletion proof that verifies the file was truly destroyed and not retained.

Is the file encrypted during transfer?

Yes. The file is encrypted in your browser before upload using AES-256-GCM. It travels over HTTPS as encrypted data and is stored encrypted at rest. Only the recipient can decrypt and download the original file.

Encrypted file transfer · Up to 30MB

Send Files Securely — Encrypted, Self-Destructing

Attach files up to 30MB, encrypted end-to-end in your browser. The link self-destructs after the first read — no copies, no traces.

AES-256-GCM encrypted
Up to 30MB file size
Destroyed after read
Optional passphrase

Send a file securely — free View pricing

How encrypted file transfer works

Attach your file

Upload any file up to 30MB. Documents, images, archives — any file type.

Encrypted in-browser

AES-256-GCM encrypts your file before upload. The key never leaves your device.

Share the link

Send the one-time link over any channel. The file travels as encrypted data.

Burned after read

File is downloaded once, then permanently deleted with an ECDSA deletion proof.

When to use encrypted file transfer

Legal documents

Share contracts, NDAs, and legal files with clients without leaving copies on email servers.

Code & credentials

Share configuration files, credentials, or codebase safely with contractors.

HR & onboarding

Share offer letters, tax forms, and personal documents with new hires securely.

Client deliverables

Send final deliverables to clients without copies living forever in inboxes.

Sensitive media

Share photos, videos, or design files that shouldn't be forwarded or stored.

Personal records

Share medical records, financial documents, or personal files with family or advisors.

How we compare to other file sharing methods

Regular file sharing leaves copies everywhere. ProtonURL encrypts and burns.

Method	Encrypted	One-time	Deletion proof	File size limit
Email attachments				25MB
WeTransfer				2GB
Dropbox / Google Drive				Large
ProtonURL				30MB

Frequently asked questions

Send your first encrypted file

Files encrypted in your browser, burned after download. Free, no account required.

Send a file securely — free