PriviTools← All tools
ESENDEPTFRIT

CALCULATORS AND OFFICE

Encrypt before sending true zero-knowledge

About to email a contract or upload your ID to the cloud? Encrypt it here first with AES-256-GCM. The recipient decrypts it on this same page with the password you share through another channel.

Free support tool — review the result

PriviTools provides this tool at no cost to make everyday tasks easier. Results are generated automatically and may contain errors, omissions or formatting changes. Compare them with the original before signing, filing, sharing or relying on them for an important decision. This tool does not replace professional review or official validation.

LOCAL PROCESSING

Everything happens in your browser

The file and text never leave your device.

Multiple files are first bundled into a ZIP and then encrypted with AES-256-GCM and PBKDF2. The key is derived and used in your browser; keep a safe copy of the password.

Download result

Select or drag a file to continue.

How to encrypt a file for free before sending it?

Select the file, type a password (or let us generate a strong one) and download the encrypted .ptenc file. Send it through any channel — email, WhatsApp, Drive, WeTransfer — knowing that without the password it is mathematically unreadable. The recipient opens this same page, picks Decrypt and recovers the original.

Serious cryptography, no servers

We use your browser's native Web Crypto API: AES-256-GCM (authenticated encryption, the banking standard) with PBKDF2 key derivation at 210,000 iterations. Unlike 'secure transfer' services, there is no server to trust: the encrypted file and the key never coexist outside your device.

Operational tip

Send the encrypted file through one channel (email) and the password through another (message or call). If you lose the password, nobody — including us — can recover the content: that is exactly what zero-knowledge means.

FREQUENTLY ASKED QUESTIONS

What is the .ptenc file?

Your original file encrypted with AES-256-GCM plus the salt and IV needed to decrypt it. Only this tool (or any implementation of the format) can open it with the right password.

Can I encrypt any file type?

Yes: PDFs, images, ZIPs, Excel… any file, limited only by your browser's memory.

What if I forget the password?

The file is unrecoverable. There is no backdoor: that's the mathematical guarantee of real encryption.

Related tools

Password Protect PDFEncrypt documents with AES-256 directly in the browser.PDF Auto-RedactorAutomatically detect and redact emails, phones, credit cards, IBAN and IDs in your PDFs.PDF Metadata RemoverAudit and wipe author, software, dates and hidden traces from your PDFs.