Protect PDF – Add Password & Security to PDF

Your PDF file and your passwords are never uploaded to any server. This tool processes everything entirely in your browser using PDF.js and a custom JavaScript PDF writer. Your passwords are only used locally to embed protection metadata into the PDF. No data ever leaves your device.

The Open Password (also called User Password) is required to open and view the PDF. The Owner Password (also called Master Password) is required to change security settings, print, copy or edit the document depending on the permissions set. You can set one or both. If only an Open Password is set, anyone with that password can view the document but cannot change security settings.

You can independently control: Printing (allow or prevent printing the document), Copying (allow or prevent text and image selection), Editing (allow or prevent modifications to the content), Annotations (allow or prevent adding comments), and Form Filling (allow or prevent filling form fields). These restrictions are enforced by compliant PDF viewers like Adobe Acrobat.

The watermark is rendered onto each page as a visible text overlay using Canvas API. You can customize the text, font size, opacity, position (diagonal, center, tiled) and color. The watermark is permanently embedded into the PDF pages and cannot be easily removed without specialized software. It is ideal for marking documents as CONFIDENTIAL, DRAFT or with your company name.

If you forget the password, there is no recovery option in this tool. This is by design — password protection is only effective if there is no easy bypass. Always keep a backup of the original unprotected PDF and store your password in a secure password manager. If you need to unlock a PDF and have the owner password, you can remove protection using PDF editing software.