PdfWox

Add a password to a PDF

Add a password to any PDF in your browser. Pick the permissions you want to restrict.

Files are processed entirely in your browser. Nothing is uploaded to any server.

About this tool

Sending a PDF that contains personal information, confidential terms, or financial data across email or a file-sharing link exposes it to anyone who intercepts or stumbles on the link. Adding an open password means only people you share the password with can read the file. Protect PDF encrypts the document with AES-256 — the same standard used by enterprise software — directly in your browser.

Beyond the open password, you can set owner-level permission restrictions: prevent printing, block text copying, or disallow further modification. These restrictions are enforced by PDF readers that comply with the specification. For maximum security, pair a strong open password with the restrictions you need — the open password is what drives the encryption strength.

Because encryption runs locally using a WebAssembly build of qpdf, the unprotected file never leaves your device. You set the password, you keep it. If you lose it, there is no recovery — so store it somewhere safe before sharing the protected document.

How it works

  1. 1

    Upload PDF

    Drop the PDF you want to protect.

  2. 2

    Set a password

    Pick a strong password and any restrictions (print, copy, modify).

  3. 3

    Download

    Download the protected PDF.

Frequently asked questions

What encryption is used?
AES-256, the modern PDF standard.
Can permissions stop a determined attacker?
Restrictions are advisory and can be bypassed by some tools. For real confidentiality, use a strong open password.
File uploaded?
No — encryption runs in your browser.
Lose my password?
We can't recover it. Save it somewhere safe.
Will Adobe Reader open it?
Yes, AES-256 protected PDFs open in all modern readers.

Related tools

Unlock PDF

Remove the password from PDFs you own.

Sign PDF

Add your signature to any PDF.

Redact PDF

Truly remove sensitive content from PDFs.

Embed this tool

Let your visitors use Protect PDF without leaving your site. Paste the snippet below into any HTML page. Files stay private — everything runs in the visitor's browser.

<iframe
  src="https://pdfwox.com/embed/protect-pdf"
  width="100%"
  height="600"
  style="border:none;border-radius:8px"
  title="protect-pdf tool"
  allow="downloads"
  loading="lazy"
></iframe>
<script>
window.addEventListener('message',function(e){
  if(e.data&&e.data.type==='privpdf-resize'){
    var f=document.querySelector('iframe[src="https://pdfwox.com/embed/protect-pdf"]');
    if(f)f.style.height=e.data.height+'px';
  }
});
</script>

The embed runs entirely in the visitor's browser — no files are uploaded. The iframe resizes automatically to fit its content via postMessage.

Deeper guide

Read the full how-to

Open the guide