Free online PDF tool
Protect a PDF with a password
A password on a PDF is the difference between a document anyone can open and one only the intended reader can. This tool applies genuine encryption to the file itself, not a cosmetic restriction that any reader can ignore.
There is something worth appreciating here: because the encryption happens in your browser, the unprotected version of your document never travels anywhere. Uploading a confidential file to a server in order to protect it has always been a slightly absurd arrangement. This avoids it entirely.
Open Protect PDFRuns in your browser — your files are never uploaded.
How to Protect PDF
- Select the PDF you want to lock.
- Choose a password and type it twice, then decide whether printing and copying stay allowed.
- Press "Protect with password" and save the encrypted file.
Frequently asked questions
What happens if I forget the password?
The file cannot be opened. There is no recovery and no back door — that is what makes the encryption meaningful. Store the password somewhere safe before you close the tab.
Is this real encryption?
Yes. The document content is encrypted inside the PDF, so a reader must supply the password to display anything. It is not a "permissions only" flag that viewers can skip.
Does the password reach your servers?
No. There are no servers involved in the operation. The password is used in your browser to encrypt the file and is never stored or transmitted.
Can I still allow printing?
Yes. Printing and text copying are separate options, so you can permit or block each while still requiring the password to open the file.
How do I remove the password later?
Use the unlock tool with the password you set.