Protect PDF
Add a password (AES-256), remove a known password, or repair a damaged PDF — with optional fast web view.
Password-protecting a PDF encrypts its contents with AES so the file is unreadable without the password — the protection travels with the file, unlike a shared-folder permission that disappears the moment someone forwards it.
There are two distinct passwords in the PDF specification. A user password is required to open the document at all. An owner password leaves it readable but restricts printing, copying and editing; that restriction is a convention that well-behaved readers honour, not a cryptographic barrier. If the content is genuinely sensitive, set a user password.
How it works
- Open the PDF you want to protect.
- Set a password to open the document, and optionally an owner password with permission restrictions.
- Choose which actions to allow — printing, copying text, annotating.
- Download the encrypted PDF.
What people use it for
- Emailing payslips or medical records where the attachment may pass through several inboxes.
- Sending a draft to a reviewer without letting them copy text out of it.
- Distributing internal documentation that must not be printed.
Frequently asked questions
- Is my file uploaded to a server?
- No. The file is opened by JavaScript and WebAssembly running inside your own browser tab. It is never uploaded, there is no server-side processing and nothing is stored — closing the tab discards everything.
- What happens if I lose the password?
- The file cannot be recovered. Encryption is done properly, which also means there is no back door here or anywhere else. Store the password before you close the tab.
- What is the difference between the two passwords?
- The user password is needed to open the file — without it the content is inaccessible. The owner password only restricts actions such as printing or copying in a document that anyone can still open.
- Do the restrictions actually prevent printing?
- In compliant readers, yes. They are enforced by the reader rather than by cryptography, so treat them as a clear statement of intent, not as a security control.
Related tools
Digital signature
Cryptographically sign a PDF with your P12/PFX certificate (PAdES) — the certificate never leaves your browser. Optional visible signature.
Unlock PDF
Remove the password from a PDF you can already open — you must know the current one. It doesn't crack protected files.
Redact PDF
Black out sensitive content with permanent rectangles you draw on the page.
Redact by search
Type words or patterns and redact every match across the entire PDF.