# Unlock PDF and password protect PDF

A PDF password remover that needs the password: unlock PDF files you can already open, or password protect PDF files with AES-256. Nothing is uploaded.

Canonical page: https://filetity.com/protect-pdf

## Capabilities

- Free: Yes, with no watermark and no page limit.
- Account required: No. There is no account system.
- Processed on device: Yes. The file is read by your browser and never uploaded. There is no server to send it to.
- Formats: PDF in, PDF out. One file at a time, in either direction.
- Limits: No page or size limit beyond the memory your device gives the browser. A new password uses AES-256. Removing a password requires that password: a wrong one is refused and no file is produced.
- Mobile: Yes, on any modern mobile browser. Large files are limited by the memory the phone gives the browser.
- Offline: Yes, after the first use. The engine is about 350 KB compressed and downloads once, then your browser keeps it, so later visits work with no network connection.

## Questions

### Can this open a PDF I do not have the password for?

No. filetity removes a password you can type in. It does not guess, brute-force or crack anything, and it is not going to. If the password is lost, this tool cannot help you, and you should be suspicious of one that claims it can.

### What is the difference between password protecting a PDF and unlocking one?

Same page, opposite directions. Protecting adds a password, so the file will not open without it. Unlocking removes a password from a file you can already open, so you stop being asked for it every time. Choose which one you want at the top of the tool.

### Does removing the password change anything else in the file?

No. The document is rewritten without its encryption rather than rebuilt, so pages, bookmarks, form fields and metadata come through as they were. Nothing is re-rendered and nothing is re-compressed.

### How strong is the protection?

AES-256, the strongest encryption the PDF format defines. The weak link is never the cipher, it is the password. A short or guessable one can be attacked offline by anyone who has the file, so pick something long.

### Can I change the password on a PDF that already has one?

In two steps. Adding a password to a file that already has one is refused, with a message telling you to remove the old one first, because the engine has to read the file before it can encrypt it again. Unlock it with the old password, then protect it with the new one.

## Related tools

- [Sign PDF](https://filetity.com/sign-pdf): Add your signature to a PDF, without uploading the document.
- [Merge PDF](https://filetity.com/merge-pdf): Combine several PDFs into a single file, in page order you choose.
- [Split PDF](https://filetity.com/split-pdf): Break a PDF into separate files, or pull the pages you need out of it.
- [Redact PDF](https://filetity.com/redact-pdf): Black out parts of a PDF so the text underneath is actually removed.