Password Protect a PDF
Encrypt a PDF with AES-256 so it needs a password to open, restrict printing and copying, or both. The file and the password stay in your browser — nothing is uploaded — and bookmarks, links, form fields and metadata all come through intact. The result is read back and checked before you download it.
Drag a PDF here, or click to browse
Encrypted and decrypted locally — the file and the password never leave your browser
Worked example: a board pack that must not leak
A 140-page board pack with a bookmark per agenda item goes out to twelve people. Set an open password (shared by phone, not in the same email), leave the permissions password blank, and keep printing allowed but copying off. The result panel confirms it refuses to open without the password, still has 140 pages and every bookmark, and lists the restrictions — then download and send.
Frequently asked questions
Is my PDF or my password uploaded anywhere?
No. The file is encrypted by pdf-lib running in your browser, and the password is used only to derive the encryption key on your machine. Nothing is sent to a server — you can turn Wi-Fi off after the page loads and it still works.
What is the difference between the two passwords?
The open password is needed to view the file at all — that is real encryption, and without it the content is unreadable. The permissions password protects the restrictions (no printing, no copying, and so on). If you leave it blank the PDF standard makes it the same as the open password, so anyone who can open the file can also lift the restrictions.
Do the restrictions actually stop someone copying or printing?
They are flags that PDF viewers agree to honour, and every mainstream viewer does. But they are not encryption: whoever knows the permissions password — or uses a tool like our Unlock page — can remove them. If the content itself must stay private, set an open password.
Which encryption is used?
AES-256 (PDF 2.0, security handler revision 6), which every viewer since Acrobat 9 (2008) opens. Choose AES-128 only if the file has to open in something older. RC4 is not offered — it is broken and was removed from the PDF standard.
Are bookmarks, links and form fields kept?
Yes. Encryption wraps the existing document rather than rebuilding it, so the outline, internal and external links, form fields and metadata all survive. The result panel counts the pages and bookmarks before and after so you can see that for yourself.
Can I change the password on a PDF that is already protected?
Yes. Upload it, enter its current password when asked, then set the new one. The file is decrypted and re-encrypted in one step, in your browser.