How do I add a password to a PDF in Adobe Acrobat?

Open the PDF in Acrobat. Go to 'Tools' > 'Protect & Standardize' > 'Encrypt'. Choose 'Encrypt with Password'. Set an 'Open Password' to view the file or a 'Permissions Password' to restrict editing/printing. Confirm and save the PDF.

What is the difference between a Document Open Password and a Permissions Password?

Password Type Purpose Access Control. Document Open Password Required to open and view the PDF. Controls who can see the document content. Permissions Password Required to change security settings or restrictions. Controls actions like printing, editing, or copying content within the document.

What level of encryption does Adobe Acrobat use for password protection?

Adobe Acrobat uses AES-128 and AES-256 encryption. AES-256 offers a higher level of security. You can choose the encryption level when setting up password protection.

Replace Old Policy Copies in Adobe Acrobat — How-to & AI prompts

AI prompts

1 way to ask · copy any one

CDecide — “help me choose”We updated the infection-control policy and training is tomorrow; I need the revised policy to…+

We updated the infection-control policy and training is tomorrow; I need the revised policy to replace older versions on shared drives so staff read the correct rules. I'm new to our intranet structure and worry I'll miss a department folder. Help me identify the likely shared locations to update, the safe file-naming and archiving steps so the old versions remain auditable, and a one-line announcement to staff pointing to the new authoritative location. I will not delete archives needed for audits.

when the reply comes backPush once: ask it to sharpen the weakest part, and to say what it assumed.

How to do it

the tool · the steps · what to avoid

1
Open the PDF file in Adobe Acrobat Pro.
2
Enter the current password when prompted to unlock the PDF.
3
Go to Tools in the top menu.
4
Select Protect from the list of tools.
5
Choose Encrypt in the Protect toolbar.
6
Click Remove Security.
7
If prompted, enter the password again and click OK to confirm removal.
8
Save the PDF to apply the changes.
Best practiceAfter removing the password, save the PDF with a new file name to keep an unprotected copy and avoid accidental overwriting.

In the appWith the API

You must know the current password to remove encryption; Acrobat cannot bypass or recover unknown passwords.

This runs in the Acrobat app - there is no separate API for this task.

Glossary

words on this page

Document Open PasswordThis password lets someone open and view the PDF file.ExampleYou need to enter the document open password before you can view the confidential report.

Permissions PasswordA password that lets you control what people can do with the PDF, like printing or editing.ExampleYou set a Permissions Password to stop others from copying text from your confidential report.

AES-256A strong type of encryption that makes the PDF very hard to unlock without the right password.ExampleA document encrypted with AES-256 requires the exact password to be opened.

Who does this

3 roles

Office AdministratorLegal AssistantRecords Manager

FAQ

about this task

Open the PDF in Acrobat.
Go to 'Tools' > 'Protect & Standardize' > 'Encrypt'.
Choose 'Encrypt with Password'.
Set an 'Open Password' to view the file or a 'Permissions Password' to restrict editing/printing.
Confirm and save the PDF.

Password Type	Purpose	Access Control
Document Open Password	Required to open and view the PDF.	Controls who can see the document content.
Permissions Password	Required to change security settings or restrictions.	Controls actions like printing, editing, or copying content within the document.

It is very important to keep an unprotected backup because if you forget the password for your PDF, there is no way to recover it from the file itself. Without a backup, you could permanently lose access to your document's content. This ensures you always have access to your information, even if you lose the password for the protected version.

Yes, you can automate this process. Adobe provides a PDF Services API that allows you to programmatically protect PDFs. You can use the 'Protect PDF' operation with endpoints like POST https://pdf-services.adobe.io/operation/protectpdf to apply passwords and set permissions for many files at once. This is useful for large batches of documents.

Adobe Acrobat uses AES-128 and AES-256 encryption.
AES-256 offers a higher level of security.
You can choose the encryption level when setting up password protection.

Replace Old Policy Copies

When to use it

AI prompts

How to do it

Glossary

The real tasks

Who does this

FAQ

Sources

Adobe help