How to password-protect Word, Excel and PowerPoint files

How to put a password on a Word, Excel or PowerPoint file

Upload the document (.docx, .xlsx or .pptx), type a password of at least 4 characters and click "Protect and download." The whole file is encrypted with the Office protection standard and, without the password, it does not open. Everything happens in your browser: neither the document nor the password is sent to any server. Files in the old format (.doc, .xls, .ppt) need to be modernized first.

1. Open the tool and upload the .docx, .xlsx or .pptx document. You can upload several at once; they all get the same password.
2. Type the password in the "Password (min. 4 characters)" field. With fewer than 4 characters, the button stays disabled.
3. Click "Protect and download" (or "Protect N files" when there is more than one). Each file is downloaded with the "-protegido" suffix in its name, such as contract-protegido.docx.
4. Keep the password somewhere safe and share it with the recipient through a different channel from the file.

What password protection is (and what changes in the file)

Password-protecting scrambles the file's content (this is called encryption) so it only becomes readable again with the right password. Once protected, opening the document in Office or LibreOffice asks for the password before showing anything. This is different from marking the file as "read only": here, without the password, the content does not even appear. The protection travels with the file, so it keeps working if the file is copied to a flash drive, saved to the cloud or forwarded.

What the tool does (and what it doesn't)

• Accepts only .docx, .xlsx and .pptx. The old .doc, .xls and .ppt formats are not accepted by the tool: convert them to the modern format first.
• Requires a password of at least 4 characters; below that, the "Protect and download" button stays disabled.
• Protects several files at once, one after the other, all with the same password; each one is downloaded separately, not as a ZIP.
• Downloads each file with the "-protegido" suffix and, when removing the password, with the "-desprotegido" suffix; the original stays untouched on your computer.
• Does not recover a forgotten password: without it, not even you can open the file again.
• Does not restrict editing or printing separately; the password is for opening the file.
• If the file is damaged or is not a real .docx, .xlsx or .pptx, you see "Could not protect the file."

Old file (.doc, .xls, .ppt)? Modernize it first

If the document is in the old Office format, the password tool does not recognize it. Convert it first to .docx, .xlsx or .pptx with the old Office formats tool (that conversion, unlike password protection, happens on our server) and then protect the modern file. The steps for that conversion are in how to convert old .doc, .xls and .ppt files to .docx, .xlsx and .pptx.

How to remove the password later

When the protection has served its purpose (the document is no longer confidential or you want to make access easier for the team), you can take the password off. Upload the protected file, type the password in the "Current password" field and click "Remove password and download"; the result comes out with the "-desprotegido" suffix and opens normally. If the file has no password, the tool says: "This file is not password-protected." If the password is wrong, you see "Incorrect password — could not open the file."

What about PDFs?

If the confidential document is a PDF, the path is the same with the PDF protection tool: a password of at least 4 characters, a "Protect and download" button and processing entirely in the browser. The difference between an open password and PDF permissions is in how to password-protect a PDF.

Things to keep in mind with passwords

• Keep the password somewhere safe: without it, not even you can open the file again.
• Send the password through a different channel from the file, never in the same email that carries the document.
• Choose a password that isn't obvious; avoid birthdays or sequences like 1234. The 4-character minimum is the floor, not the goal.
• Check the protected file before sending it: open it, type the password and make sure the content shows up.

A common case: you need to send a spreadsheet with payroll, a customer list or financial figures. Protect the file before attaching it to the email and share the password by message or phone call. That way, even if the email lands in the wrong hands, the content stays locked.

Everything happens in your browser: the document is protected and unprotected on your own device and is never sent to any server; the password does not leave your device either.