Protect PDF with a password
Protect a PDF with a password so it can only be opened with it.
Drop your file hereTap to choose your file
or click to choose · paste with Ctrl+VPDF · up to 300 MB
Processed on your device: nothing is uploaded
A password was generated and entered in both fields. Copy it and keep it somewhere safe before continuing.
Advanced options
It lets you change the permissions later. If you leave it empty, a random one is generated and no one will be able to remove the restrictions. It must be different from the open password.
Protected PDF
Verified: the new PDF asks for a password and opens with the one you chose.
Save the password
If you forget it, no one will be able to open this file: there is no way to recover it. Keep the original PDF too.How to use it
- Drop your PDF into the box or choose it from your device.
- Enter the password and repeat it. The meter tells you how strong it is, or you can generate a strong password with one click.
- If you want, limit what can be done with the file: printing, copying the text, or editing it.
- Select “Protect PDF” and download the file. Keep the password somewhere safe: it cannot be recovered.
Frequently asked questions
Are my PDF or my password uploaded to a server?
No. The encryption happens inside your browser with a tool that downloads together with this page. Neither the file nor the password leaves your device.
How secure is the protection?
It uses AES-256 encryption, a widely used security standard. The real strength depends on the password: a long one that is hard to guess is practically impossible to break by brute force.
What happens if I forget the password?
There is no way to recover it. No one, including this page, can open the file without it. Keep the password in a password manager or write it down in a safe place, and keep the original unprotected PDF.
What are the print, copy, and edit permissions for?
They are restrictions that most viewers respect, for example so a contract can be read but not printed. They are not a strong barrier: anyone who can open the file can get around them with specific software. What really protects the content is the password to open it.
What is the difference between AES-256 and AES-128?
AES-256 is more secure and accepts any character in the password. AES-128 is compatible with very old viewers, but it only accepts up to 32 characters from the Latin alphabet. If you have no reason to use AES-128, leave AES-256 selected.
Will it open on my phone and in any program?
Yes. Files with AES-256 open in current browsers, Adobe Acrobat, and the PDF viewers on Android and iOS once you enter the password.
When to protect a PDF
Before sending a contract, a pay stub, a medical report, or any document with personal data by email or messaging, it is a good idea to encrypt it. That way, even if the file ends up in the wrong hands, it cannot be read without the password.
How to choose a good password
- Length over complexity: a phrase of four or five unrelated words is stronger and easier to remember than “P@ssw0rd!”.
- Do not reuse it: use a different one for each important document.
- Send it another way: send the PDF by email and the password by text message or phone.
After protecting
If you later need to remove the password, use “Unlock PDF” with the correct password. To show who a document belongs to, add a watermark to it first.
Updated on September 29, 2026