Protect PDF
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Protect your PDF with a password. Type one, then download a locked copy that needs it to open. Free, no account, and your file never leaves your device.
Stays on your device
A $6 day pass gives you 24 hours of server tools. You pay once, and it does not renew. Pricing
How to password protect a PDF
This tool puts a password on your PDF so only people who know it can open the file. Type the password you want, then start. The file is locked with AES-256, a strong and widely used type of encryption. Anyone who opens the new file must type the password first. The same password also controls the file's security settings, so keep it somewhere safe. The password box hides what you type, and your browser is asked not to save it. Any characters work. You download one PDF named protected.pdf, and it is still a normal PDF. Your original file is not changed. We do not add a watermark or a logo.
Your file stays on your device. It is never uploaded, and your password is never sent anywhere. You can check this yourself: open your browser's developer tools, go to the network panel and add a file. No upload appears. There is no sign-up, and when you close the page the copy in your browser is gone. Need to remove a password later? Unlock PDF does that when you know it.
There is no page limit and no daily limit. A long PDF works as long as your device has enough memory to open it. Very large files, such as scans with hundreds of pages, can be slow on a phone or an older laptop. If your device runs low on memory, close other tabs or try a smaller file.
If you see a message asking you to choose a password, the box was empty. Type a password and try again. If the page says it could not protect the PDF, the file may be damaged, so try another copy. A PDF that already has a password must be unlocked first with Unlock PDF. This page only adds a password. It cannot remove or guess one.
How to use this tool
- Choose your file. It never leaves your device.
- Pick a setting, if the page has one.
- Download your new file.
Common questions
How do I put a password on a PDF?
Add your file, type the password you want in the box, and start. The new file asks for that password every time someone opens it. It cannot be empty, and there is no set limit on length. We never see your password, so we cannot recover it. Save it in a password manager.
Is my PDF uploaded when I protect it?
No. Your file stays on your device. It is never uploaded, and neither is your password. Your download is protected.pdf. Only PDF to Word, OCR PDF and heavy compression send files to our server.
Can I take the password off later?
Yes, if you know it. Use Unlock PDF and type the password. No tool on this site breaks or guesses passwords, so keep your password safe.
Is it free to password protect a PDF?
Yes, it's free. No account, no daily limit, no watermark.