Encrypt Word documents and add watermarks without uploading them

Set or remove the open password of a Word .docx file, add a native Word text watermark, write copyright information and restrict editing — all inside your browser.

Encryption uses the same ECMA-376 Agile Encryption as Office 2013 and later (AES-256-CBC with SHA-512 key derivation and an HMAC integrity check), so the file opens with its password in Microsoft Word, WPS and LibreOffice. Every operation runs in your browser using WebAssembly and Web Workers. Your file is never uploaded to a server, so nothing can leak, be logged, or be used to train anything.

• Open password with Office-compatible AES-256 encryption
• Remove a password you already know and export a plain .docx
• Native Word text watermark (diagonal or horizontal, color, opacity, size) written into every section header
• Copyright notice as a custom document property, optional copyright line in the footer
• Remove author, last-modified-by, company and reviewer names
• Restrict editing to read-only, comments, tracked changes or forms, with an optional password

FAQ

Will Microsoft Word open the encrypted file?

Yes. The tool writes the standard Agile Encryption container that Word 2010 and later use, so Word asks for the password and opens the document normally.

Is restrict editing the same as encryption?

No. Restrict editing only limits changes inside Word; anyone can still read the content. Use the open password if others must not read the file.

Can it remove an unknown password?

No. You can remove a password you already know. The tool does not crack passwords.

Are old .doc files supported?

Only .docx is supported. Save a .doc file as .docx in Word first.

Related Pages & Tools

• PDF Security & Watermark
• Word Reader
• Word & Markdown to PDF
• Document Compare