Tool Fu
$ toolfu run encrypt-pdf

Encrypt PDF — Password Protect PDF Files Online Free

Add password protection to PDF files online for free. The output works in any PDF reader. 100% client-side — your files never leave your browser.

all processing runs in your browser
encrypt-pdf
input > select a PDF to encrypt

$ drop a PDF file here or click to browse

select a PDF to add password protection

or paste from clipboard (⌘V / Ctrl+V)

Adds standard PDF password protection. The output works in any PDF reader (Acrobat, Preview, Chrome, etc). 100% client-side — your files and password never leave your device.

Encrypt PDF Online

Add standard password protection to your PDF files, entirely in your browser.

Features

  • Standard PDF encryption — works in any reader
  • 100% client-side — nothing uploaded
  • Set a password to restrict access
$ cat FAQ.md
How is the PDF encrypted?
Standard PDF password protection is applied. The output is a normal .pdf file that any PDF reader (Acrobat, Preview, Chrome, etc) will prompt for a password before opening.
Can I open the encrypted file in any PDF reader?
Yes. The output uses standard PDF encryption compatible with all major PDF readers.
Are my files uploaded?
No. Encryption runs entirely in your browser. Your files and password never leave your device.
What happens if I forget the password?
There is no recovery. The file cannot be opened without the correct password.