Protect PDF
PDF & DocumentsAdd a password and encryption to keep a PDF private.
What is Protect PDF?
Protect PDF adds a real password to a PDF, so anyone who opens it — in Acrobat, Preview, Chrome, or any standard reader — has to type the password first. The file is encrypted with AES-256 using the PDF standard security handler, and all of it happens inside your browser tab: your document and your password are never uploaded, never logged, and never leave your device.
How to use Protect PDF
Add your PDF
Drop a PDF in or click to browse. It's read straight into this browser tab — nothing is sent to a server.
Choose a password
Type the password you want readers to enter. It must be at least 8 characters, and a strength meter shows how solid your choice looks as you type.
Confirm it
Re-enter the same password in the confirm field. Since a forgotten password can't be recovered, this catches typos before the file is encrypted.
Protect and download
Click Protect & download. The PDF is encrypted in your browser and saved as <name>-protected.pdf, ready to send.
Test before you share
Open the downloaded file in your PDF reader and check it asks for the password. Store the password somewhere safe — a password manager is ideal.
Common uses
- Email a contract, invoice, or payslip without leaving it readable to anyone who gets the file
- Protect scanned ID documents, bank statements, or medical records before sharing
- Lock a confidential report so only the intended recipients can open it
- Add a password to tax paperwork before sending it to an accountant
- Keep sensitive HR or legal documents private in shared cloud storage
- Secure a PDF on a USB stick or external drive in case it's lost
Why choose Super File Tools
Privacy-first
Most tools process your files inside your browser and never upload them to a server.
Free, no account
No sign-up, no watermark, no paid tier. Just open a tool and use it.
Instant
For local tools, work starts the moment you drop a file — no upload or queue.
Runs in your browser
Most tools are built on open web standards and work on any modern desktop browser.
No upload size caps
For local tools, nothing leaves your device, so the only limit is your machine’s memory.
Yours to keep
Results download straight to your device in clean, standard file formats.