Encrypt your PDF with bank-grade AES-256 security.
or click to browse from your computer
Files encrypted & deleted after processing.
Secure AES-256 for max protection.
Free to use, 100% online.
Secure your confidential documents in seconds. Add a strong password that encrypts your file contents completely.
Drag & drop your PDF. Connection is encrypted with TLS 1.3 for maximum safety.
Choose a strong password. You can also set a separate 'Owner Password' for permissions.
Download your protected file instantly. It can now only be opened with your password.
Because we use strong encryption, if you lose your password, the file cannot be recovered. We do not keep a copy of your password.
We treat your privacy as our top priority. Our tool uses **AES-256**, the Advanced Encryption Standard used by governments and banks worldwide.
Unlike basic password tools that just add a flag, we fundamentally rewrite the PDF structure, wrapping every byte of data in a cryptographic layer that is mathematically impossible to brute-force with current technology.
Processing happens in isolated, ephemeral containers that are destroyed immediately after your file is ready. Your data never rests on our servers.
The highest standard of encryption available publicly.
We don't store your files or your passwords. Ever.
Files destroyed upon job completion.
Sending sensitive data like bank statements, contracts, or personal ID documents via email is risky. If your email is compromised, your data is exposed.
PDF Lock solves this by wrapping your file in a layer of mathematics. Even if a hacker intercepts the file, they only see random noise without the correct password.
Start PDF Lock supports two types of passwords:
Advanced Encryption Standard (256-bit). The same encryption used by the US government for top-secret information.
The secret string of characters (derived from your password) used to scramble and unscramble data.
Settings that control what a user can do with a PDF (Print, Copy text, Edit, etc.).
A hacking method of trying every possible password. AES-256 is resistant to this.
Length beats complexity. "Correct-Horse-Battery-Staple" is harder to crack than "Tr0ub4dor&3" and easier to remember.
If you want to allow someone to read but not print, give them the User Password but keep a different, stronger Owner Password for yourself.
Your documents are processed in secure, isolated containers and are permanently deleted immediately after processing.
Enterprise Grade"Finally, a tool that actually encrypts files securely. I trust this for my contracts."
"Great for sending employee data safely. I love the separate admin password feature."
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