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Protect PDF
Encrypt a PDF with a password and set print/copy permissions.
Free, no uploads, no sign-up. Runs 100% in your browser.
How Protect PDF works
Protect PDF runs entirely in your browser. Encrypt a PDF with a password and set print/copy permissions. Under the hood it uses @cantoo/pdf-lib (a pdf-lib fork that can read and write password-encrypted PDFs), pdf-lib (a pure-JavaScript library that creates and edits PDF structure (pages, text, images, forms)) and PDF.js (Mozilla’s PDF renderer, used for thumbnails, previews and text extraction (runs in a Web Worker)). Your files are read into this tab’s memory, processed on your own CPU, and handed back to you as a download. Nothing is sent to a server.
Input: PDF.
How to use Protect PDF
- Drop a PDF.
- Enter an open password (and optionally an owner password).
- Choose permissions such as printing or copying.
- Encrypt and download.
Tips
- Store the password safely. Nobody, including OpenFile, can recover it.
Protect PDF FAQ
- Are my files uploaded?
- No. This tool runs entirely in your browser tab. Files are read from your disk into memory and the result is generated locally.
- Is it free? Are there limits or watermarks?
- Free and open source (MIT). There are no file-size caps, daily quotas, accounts or watermarks.
- Does it work offline?
- Yes, once the page (and any engine it needs) has loaded, it keeps working without a connection thanks to the service worker cache.
Related tools
- Unlock PDF: Remove the password from a PDF you have access to.
- Redact PDF: Black out areas or auto-find emails, phones and card numbers, then flatten.
- Watermark PDF: Stamp text or logo watermarks with opacity, rotation and tiling.
- Merge PDF: Combine multiple PDFs into one ordered document with drag-and-drop sorting.