Free PDF tool
Protect A PDF With A Password
Encrypt a document before you send it anywhere.
Emailing a document with a bank account, a medical detail or an ID number on it means handing a readable copy to every mail server along the way. A password turns it into something only the intended reader can open.
This uses AES-256, the same encryption standard as the rest of our security tools, applied by a WebAssembly build of qpdf running in your browser. You can also set permissions — whether readers may print, copy text or edit — which viewers honour by convention.
How to use it
- 01Drop in the PDF you want to protect.
- 02Choose a strong password and confirm it. The strength meter is a guide, not a gate.
- 03Optionally set an owner password and decide what readers are allowed to do.
- 04Encrypt and download the protected document.
Frequently asked questions
What happens if I forget the password?
The document is unrecoverable. AES-256 has no back door and neither do we — nothing about the file is stored anywhere. Keep the password in a password manager before you send the file.
How strong is the protection really?
The encryption is strong; the password is the weak point. A short or common password can be guessed offline at enormous speed, which is why the tool warns about weak ones. Use a long random passphrase for anything sensitive.
Are the permission settings actually enforced?
They are honoured by mainstream PDF readers, but they are a convention rather than a cryptographic guarantee — the content is decrypted once the file is open. The password is the real control; permissions are a clear statement of intent.
What is the difference between the two passwords?
The first is needed to open the document. The owner password controls the permissions and lets its holder change them. Leaving the owner field blank reuses the open password, which is fine for most uses.
Related tools
- Unlock PDFRemove a password you know from a PDF, so it opens without one.
- File EncryptionEncrypt a file with a passphrase before uploading it anywhere — AES-256-GCM, fully local.
- Secure Password GeneratorGenerate a strong random password, with the length and character set you choose.
- PDF Metadata Viewer & EditorSee and edit the author, title and software recorded inside a PDF — or strip it.
This is what Purgify automates.
Connect your cloud accounts and Purgify finds duplicates and reclaimable space like this — across all of them, on a schedule.
Want early access? Write to us at [email protected]