More in Edit & Security
About this tool
A closer look at Protect PDF
Protect PDF encrypts a PDF with a password using local browser encryption. Set a password of at least 8 characters, confirm it, and download the protected file. The password is applied in your browser and is never sent anywhere.
An encrypted PDF cannot be opened without the password, which is the meaningful protection for sensitive files sent by email, stored on shared drives, or handed to clients. Permission restrictions such as 'no printing' can be requested alongside, but reader support varies and the password is the primary protection.
The encryption runs locally with the Open Password set; you can later remove it with the Unlock PDF tool when you have the password. Because protection is one-way, keep an unlocked backup if you may need to edit the file again.
Supported files
How to use it
- 1Upload PDF
- 2Enter password
- 3Download protected PDF
What you can use it for
- Adding password protection before sending a sensitive file.
- Protecting files you store on shared drives.
- Enforcing a password on client-facing documents.
- Checking a file stays unreadable without your passphrase.
What to keep in mind
- Passwords must be at least 8 characters.
- Encryption is applied locally with a single user/owner password.
- Restrict printing/copying/editing options are best-effort; support varies by PDF reader.
- Encrypted PDFs must be unlocked with Unlock PDF before further editing.
- A forgotten password cannot be recovered — there is no server copy to restore from.
Troubleshooting
The file still opens without a password
Make sure the password was set on the downloaded PDF — the tool protects the version it exports, not the original file on disk.
Printing restrictions do not take effect in some readers
Restriction flags are best-effort and reader-dependent. The open password is the reliable control; share it only with intended recipients.
An unlocked tool refuses the file
Unlock it first with Unlock PDF, then process the unlocked copy.
Related tools
Frequently asked questions
What is the minimum password length?
8 characters. Aim for a passphrase of 12+ characters mixing words, numbers and symbols for stronger protection.
Is my password sent anywhere?
No — encryption and restriction flags are applied locally in the browser.
Can readers still print or copy the file?
Restriction flags are best-effort and support varies between PDF readers; the password is the primary protection.
What happens if I forget the password?
The password cannot be recovered. Keep an unlocked backup copy if you may need to edit the file again.
Can I remove the password later?
Yes — the Unlock PDF tool removes the password from a copy of the file when you enter the correct password.