Protect a PDF with a password, for free

Add a real opening password to your PDF — no one will be able to open it without it.

🔒 100% private — your file and your password are processed on your device and never uploaded to any server.

A real password, not just a visual lock

This tool encrypts the PDF file itself (128-bit RC4 encryption, the PDF format's own standard) — it isn't just about locking a web page, the file you download really is protected. Open it with Adobe Reader, Mac Preview, Chrome's built-in viewer, or any other PDF-compatible program: all of them will ask for the password before showing the content.

Keep your password safe

Because this is real encryption, there's no "back door": if you forget the password, the file becomes permanently inaccessible, even to us — we never receive it or store it anywhere, the whole process happens in your browser. Write it down somewhere safe before downloading the protected PDF.

What permissions the resulting PDF has

Besides asking for a password to open, the protected PDF restricts editing and copying its content, but still allows printing — meant for a file you want to share securely without it being modified.

Frequently asked questions

What kind of protection is this?

Real encryption (128-bit RC4) of the PDF file itself, per the official PDF standard. Any program that opens PDFs — Adobe Reader, Preview, your own browser — will ask for the password before showing the content.

What happens if I forget the password?

There is no way to recover it or to open the file without it — we never store it anywhere, so not even we can help you recover it. Write it down somewhere safe before downloading the protected PDF.

Is my PDF uploaded to a server?

No. The encryption happens in your browser — your file and your password are never transmitted anywhere.

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