What kind of encryption does this use?

This tool applies standard PDF encryption to the file, which is the same protection mechanism supported by mainstream PDF readers like Adobe Acrobat — the resulting file requires the password in any compliant PDF viewer, not just this site.

Can I restrict printing or copying without requiring a password to open the file?

Yes — permission restrictions (like disallowing printing or text copying) can be set independently of the open password, using a separate owner-level password that controls what's allowed once the file is opened.

What happens if I forget the password I set?

There is no recovery mechanism — password-protected PDFs are designed so that only someone with the correct password can open them. Keep a record of the password somewhere secure, since it can't be recovered from the file afterward.

Will password protection work on a PDF that already has form fields or signatures?

Yes, encryption is applied to the file as a whole and doesn't interfere with existing form fields, though some permission restrictions can limit whether those fields remain fillable, depending on the options you choose.

Does encrypting the file change its content or formatting?

No, encryption only controls access to the file — the underlying pages, text, and images are stored exactly as they were, just wrapped in password protection.

Can I later remove the password if I no longer need it?

Yes, use the Unlock PDF tool with the correct current password to remove protection and get back an unencrypted file.

Is my file uploaded to a server?

No. Every operation on this page runs locally in your browser using JavaScript and WebAssembly. Your file, and the password you set, are never transmitted anywhere.

Password Protect PDF

Encrypt a PDF with a password and set printing, copying, and editing permissions.

Processed entirely in your browser — your file is never uploaded anywhere.

Why password protect PDFs with Tools Root

Sensitive documents — financial records, contracts, personal information — often need to be shared over channels that aren't fully private, like email. A password requirement means the file itself carries its own protection, independent of how it's transmitted.

Real, standards-compliant encryption

This uses a genuine PDF encryption implementation, via a fork of the pdf-lib library with real encrypt and decrypt support, rather than a superficial lock that only this site recognizes. The resulting file requires the password in Adobe Acrobat, Preview, or any other standards-compliant PDF reader.

Common use cases

Protecting a PDF containing financial statements before emailing it to an accountant, restricting printing on a document you're sharing for review only, adding a password to a legal contract before it's transmitted, or securing a file that will be stored somewhere outside your direct control.

How to password protect a PDF

1Upload the PDF you want to encrypt.
2Set the password required to open the file.
3Optionally restrict printing, copying, or editing permissions independently of the open password.
4Download the encrypted PDF.

Frequently asked questions

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