Protect PDF
Choose a PDF, type a password, and download an encrypted copy that asks for the password before it opens. Your file stays in your browser.
How to password protect a PDF
- Select Choose a PDF, or drop a PDF file on the box. The tool protects one PDF at a time, up to 100 MB.
- Type the password under Password, then again under Confirm password. You can use A–Z, a–z, 0–9, spaces, and keyboard symbols, up to 127 characters. Select the eye icon in the field to check what you typed.
- Select Download protected PDF. The copy keeps the original name with -protected added, such as report-protected.pdf. Your original file isn't changed.
- Before you send the file, open it once with the password to make sure it works.
What the password protects
The tool adds an open password, also called a user password, and encrypts the file with AES-256, the encryption defined in the current PDF standard (PDF 2.0). PDF readers ask for the password before they show any page. To see how an open password differs from a permissions password, read about PDF password protection.
The same password is also set as the permissions password, with every permission allowed. Anyone who opens the file can print it, copy text, fill in forms, and edit it. The tool doesn't add print or copy restrictions, because they only work when the reader honors them and many apps ignore them. The open password keeps the content private.
Passwords are limited to A–Z, a–z, 0–9, spaces, and keyboard symbols. PDF 2.0 allows other characters, but readers don't handle them the same way. Preview on Mac, for example, can't open a file whose password contains é, ö, Korean letters, or full-width characters. PDF 2.0 also reads only the first 127 bytes of a password, so the limit is 127 characters.
To protect several PDFs as one file, combine them first with Merge PDF. To remove, reorder, or rotate pages before you add a password, use the PDF page organizer.
Frequently asked questions
Is it free to password protect a PDF here?
Yes. There's no signup and no watermark. You can protect as many PDFs as you like, one at a time, each up to 100 MB.
Is my PDF uploaded?
No. Your browser encrypts the PDF on your device. Neither the file nor the password is sent to a server, and closing the tab clears both.
How secure is AES-256 encryption?
AES-256 is the strongest encryption the PDF format supports, and without the password the pages can't be read. The password itself is the weak point: a short or common one can be guessed, so use a long passphrase or one generated by a password manager.
Can people still print or copy text from the PDF?
Yes. Once someone opens the file with the password, they can print it, copy text, fill in forms, and edit it. The tool doesn't set a separate permissions password.
What if I forget the password?
Shotomatic can't recover or reset it, because the password never leaves your browser. Keep the original unprotected file, or save the password in a password manager.
Why can't the password include accented letters or other scripts?
PDF readers handle these characters differently, so a password that works in one app can fail in another. Preview on Mac, for example, can't open a file whose password contains é, ö, or Korean letters. A–Z, digits, spaces, and keyboard symbols are read the same way by every PDF reader.
Why does it say my PDF is already encrypted?
The PDF already has an open password or editing restrictions. Remove them in the app that added them, save an unprotected copy, and protect that copy here.
Sharing screenshots as a PDF?
Shotomatic captures a whole screenshot series on your Mac and exports it as one PDF. Add a password to that PDF here before you send it.