PDF / Password
Protect PDF: Add a Password with AES-256 Encryption
Password-protect a PDF in your browser: the file is encrypted with AES-256 so it opens only with the password, and you can also limit printing, copying, and editing; nothing is uploaded, so the document and the password stay on your device.
Protect PDF: Add a Password with AES-256 Encryption: The PDF is encrypted with the AES-256 method of PDF 2.0 (security handler revision 6), which every current PDF reader opens, using qpdf compiled to run in your browser. The open password is needed to read anything in the file. Restrictions on printing, copying, and editing are stored with a second password; if you do not set one, a random one is used and shown to you once. Runs 100% locally in your browser with zero server file uploads.
- Category
- PDF tools
- Runs
- In your browser
- Cost
- Free · no sign-up
- Availability
- Ready to use
Runs entirely in your browser
Up to 100 MB · nothing is uploaded
Encryption runs in your browser with qpdf, free software under the Apache License 2.0, loaded as a separate file the first time; your PDF and password are never uploaded.
A strong password
The encryption is only as strong as the password. Use at least 12 characters, or four or five random words, and send it to the recipient separately from the file.
Open password and restrictions
The open password is required to read the file. The restrictions password only controls printing, copying, and editing once the file is open, and is needed to remove them.
How to use it
- Choose a PDF.
- Type the password twice, and untick anything people should not be allowed to do once it is open.
- Protect the PDF and keep the password somewhere safe.
Privacy & limitations
Your PDF and password stay in your browser and are never uploaded.
Related tools
Frequently asked questions
Can a forgotten password be recovered?
No. AES-256 has no back door, and nothing is stored anywhere, so keep the password safe.
Do the restrictions really stop copying?
Mainstream readers honour them, but they are a request rather than a lock: anyone who can open the file could remove them with other software. Only the open password truly protects the content.
Will it open on phones and older readers?
Any reader from the last decade or so opens AES-256 PDFs, including the ones built into browsers, Windows, macOS, iOS, and Android. Some very old software only supports the weaker 128-bit methods.
Free tool · runs in your browser · no account required