Protect and compress your PDF documents

Password protect and redact important documents, and optimize file size with compression.

Published December 22, 2025

00:01

Introduction

PDF files are a very useful format for storing and sharing sensitive information, but it's important to make sure these files are protected and optimized.

I'm Sarah, and I'm going to show you how Adobe Acrobat can help you do that.

The easiest way to add security to a PDF file

00:13

Protecting PDFs with passwords

is by using the Protect tool.

This tool lets us add a password to control who can access a file, as well as control the levels of access granted to anyone who does have the password.

To get started, select the Protect tool in the All tools menu and then open the PDF.

In the side menu, click Protect with password.

On this pop-up, we can choose whether we want to grant Viewing or Editing access with this password.

00:43

Applying advanced encryption and access restrictions

To add further layers of security, we can select the Advanced Options menu and choose Encrypt with Password or Encrypt with Certificate.

With either of these options, we'll be required to choose the level of protection by checking one or both of the following boxes: Require a password to open the document or Restrict editing and printing of the document.

The second option includes the ability to restrict the copying of text and images, or deny screen reader devices access to the text.

Next, choose the minimum version of Acrobat recipients can use to view the file.

Then we'll pick which type of content we want to encrypt and select OK.

Now we'll get a few pop-ups asking us to confirm the passwords we've set and reminding us to store them somewhere secure.

We'll also see a warning that while Adobe products will enforce the chosen restrictions, it's possible some third-party products will not.

So, keep that in mind.

Once finished, the privacy settings will be applied when the document is saved.

If we decide later that we'd like to remove these security settings, we can easily do so by clicking the Remove security button in the sidebar here.

01:57

Compressing PDFs to reduce file size

Now let's talk about optimization.

PDFs are meant to be a quick way to share information, and optimization helps keep them a manageable size while still maintaining their quality.

The simplest way to compress the size of a PDF is by using the Compress a PDF tool.

This is the recommended method unless we have an advanced understanding of the elements of our document.

Select the Compress a PDF tool in the Tool menu and then open the PDF.

Under Reduce File Size in the sidebar, we can choose to compress a single PDF, or select multiple files to combine and compress into one document.

For this example, we'll choose Single file.

On the pop-up, choose where to save the file by selecting an option from the most recent save locations, or by clicking Choose a different folder.

We also have the option to convert the file to a number of other file types.

Once we've made our choices and named the new optimized version, the document will be saved.

If we need to further customize the optimization, we can do that using the Advanced Optimization options.

03:00

Using advanced optimization settings

Here, we can be more selective about the types of content being optimized and by how much.

Choose the Compression options that fit the document's needs and click OK.

Select a location to save the file and then click Save.

This will help keep documents safe, secure, and the right size to send when the time comes.

Thanks for watching.

Note: Stock assets provided are for practice purposes only. See terms.

What you’ll learn

Protect your PDF documents

Add password protection, encryption, and set viewer permissions to your documents using the Protect a PDF tool.

Optimize file size

Reduce file size and improve loading times without losing quality using the Compress a PDF tool.

Instruction by: Sarah John
Adobe Stock Contributor: ContestDesign

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