Password-protect a PDF with AES-256 encryption and choose whether people can print, copy or edit it. The file is encrypted in your browser and never uploaded.
Works in your browser. What you paste or upload is processed on your device.
Choose or drop the PDF you want to protect.
Type the password people will need to open it, then type it again.
Decide whether printing, copying, commenting and editing are allowed. Add an owner password if you want to change them later.
Press Protect PDF and save the encrypted copy. Share the password separately from the file.
Protect PDF encrypts a PDF so it can only be opened with the password you choose. It uses @cantoo/pdf-lib in your browser with AES-256 by default, the strongest standard PDF encryption, which every current PDF reader supports. AES-128 is available for very old readers. The tool checks that the encrypted file opens with your password before it hands it over.
You can also set permissions: allow or block printing (or allow low-quality printing only), copying text and images, adding comments and filling forms, and editing the document. These are stored under a separate owner password. If you leave the owner password empty, a long random one is generated, so the restrictions can't be lifted with the open password.
Be realistic about permissions: Acrobat, Preview, Chrome and most readers respect them, but some tools ignore them once the file is open. The open password is the real protection. Choose a long one and keep it safe, because nobody, including us, can recover it.
Contracts, payslips, medical reports and statements often travel by email or chat, where they can be forwarded or left in shared folders. A password means only people you give it to can read the document. Doing it in your browser also means the unencrypted file is never sent to a third-party server to be encrypted.
Something else? Ask the team
It uses AES-256, the strongest encryption in the PDF standard. In practice the password is the weak point, so use at least 8 characters with a mix of letters, numbers and symbols, or a long passphrase.
No. Encryption happens in your browser. The original and the protected file both stay on your device.
It controls the permissions (print, copy, edit). Someone who opens the PDF with the owner password can change or remove them. If you leave it empty, a random owner password is set so the restrictions stay in place.
It can't be recovered, by us or anyone else. Keep a copy of the unprotected original somewhere safe, or store the password in a password manager.
Yes. Open this page in Safari, choose the PDF from Files, set the password and download the protected copy back to Files. It also works in Chrome on Android.
Yes. AES-256 PDFs open in Adobe Acrobat Reader, Apple Preview, Chrome, Edge, Firefox and the built-in readers on iPhone and Android. Choose AES-128 only for software older than about 2008.
You get 1 free run of this tool per day. After that, each run costs 5 credits from a free AI Rank Lab account (1 credit is 1 US cent). A run is one press of the main button; changing options, previews and editing before that are free. If a run fails, it is handed back automatically.
Each one opens on its own page and works straight away, with no sign-up.
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