How to Add Comments in PDF in a Few Minutes

While reading PDF documents, if you want to add comments in PDF to remember while doing the revision, but don't know how to do that, this article gives you a detailed guide to add comments in PDF on Windows and Mac. You can add highlights, sticky notes, underline, strikeout, text, stamps, and shapes to mark up the important info with UPDF. Let's dive into the details.

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Part 1: Why Can't I Add Comments in PDF?

Many users find it difficult to add comments in PDF files for some reason. As a result, they are unable to do their quick revisions and lack comprehension of concepts quickly. Some of the reasons are:

  • There are many PDF tools that do not allow adding comments on the files automatically. Or in another case, some tools lack the feature for adding comments on PDF files directly. Due to the restriction from a particular PDF tool, you would be unable to add comments on the files consequently.
  • Another major reason is that many files limit the editing process while adding comments on them. As a result, you may enter comments on the file but would find difficulty in editing the document, such as adding pages or typing content.
  • Some tools may allow you to add comments but only in a separate copy. It means that if you want to add a comment, the tool would require you to make a copy of the file first, and then it will allow you to comment properly.

Part 2: How to Add Comments to PDF on Windows?

UPDF provides a coherent set of features to add comments across a PDF document. As it is essential to add comments on PDF documents to present proper feedback, you must follow the provided guidelines to add the comments on UPDF for your Windows device:

Step 1. Import PDF File

As you have opened the PDF document on UPDF, click the "Comment" tab from the left panel.

how to add comments in pdf comment icon

Step 2. How to Add Comments in PDF Files

Add a "Text Comment"

This opens up a menu providing the commenting features offered by UPDF. Select the "Text Comment" button from the top to add a comment on your PDF. Set the font style, size, and color as you tap anywhere on the PDF to add the comment. Write down the comment and add it to your PDF.

add comments to pdf text comment button

Add a "Text Box"

You can also add a "Text Box" as a comment on your PDF document in UPDF. As you select the button from the top, tap anywhere on the PDF where you want to add the comment. Following this, specify the style of the text box and define the parameters for the font style, size, and color. Write down the text in the box and conclude by adding a comment.

add text box

Add a "Sticky Note"

UPDF also offers you to add a "Sticky Note" as a comment on the PDF document. Select "Sticky Note" from the top buttons and tap where you want to add it to the document. Type in the text across the note that opens on the screen and changes the color if you wish to.

how to insert comment in pdf add sticky note

Video Tutorial on How to Add Comments to PDF

Part 3: How to Insert Comments in PDF on Mac?

If you are a Mac user, there is also a great choice for you to add comments in PDF. That is also UPDF, a fast PDF annotator, which has various annotation tools. Apart from editing your PDF document professionally through this powerful tool, you can add comments comfortably to the document with a single click.

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add comment to pdf on mac in updf

Through its exclusive features, make your comments highlighted by underlining, striking out the text, and adding text boxes. Other distinct features of this tool that makes it extraordinary are an easy-to-use interface and responsive speed while editing. You can utilize this tool and can enjoy the editing experience in a secure environment. Hence, it's an exceptional tool for Mac users as it offers great reliability.

Steps to Insert Comment in PDF on Mac Using UPDF

Step 1. Launch the UPDF

Begin with launching the UPDF tool on your computer and open its main interface. To import the PDF file, click on "Open File" and select the document you want to edit.

Step 2. Select Comment Tool

Navigate to the "Comment" icon displayed on top and click on it to open options for adding annotations.

insert comment in pdf comment button

Step 3. How to Add Comment on a PDF on Mac

Tap on the icon of "Sticky notes" and click on a particular part of the document where you want to add the comment. Afterward, add the text on the displayed text box of the sticky note and click enter to post the comment on your file quickly.

how to add comments in pdf file on mac

Besides this tool for Mac, if you want to learn more about other tools to add comments to PDF on mac, there are the top 5 PDF annotators for Mac, making you process more opportunities to choose a proper tool.

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Part 4: What Types of Comments Does UPDF Support?

UPDF provides the option of adding three types of comments within PDF documents. We have set up an introduction of these types along with the significance they present within the document:

  • Text Comment: These are simple lines of comments that can be added and adjusted across a document. This is usually considered an informal form of adding comments in a PDF document, where you type in the text corresponding to the content written in the PDF file to let the author know about the problems that you might have.
  • Text Box: Such forms of comments are considered more professional and elegant. Having the problem written in a text box helps people differentiate the points correctly. Professional and official documents usually contain such forms of comments on the documents.
  • Sticky Notes: If you do not want to cover the PDF document with text comments and boxes, it is best to use a sticky note. With the details of the user that is adding the note, it does not disrupt the outline of the PDF document.

Part 5: How Does Commenting in PDF Help Users?

There are some specific reasons why commenting has been added to PDF documents. Although this has been an everchanging feature in PDF editors, there were some potential reasons why it was added to the platforms:

  • Using comments to explain a particular point removes the ambiguity that remains between both parties. One party can define the parameters and pointers properly to the other party.
  • Marking something without getting it printed saves paper which is good for the environment and the office in terms of cost. Documents can be managed digitally without printing them out.
  • These documents that are commented on can be shared with a diverse set of users. Where printed documents are restricted within the location, digitally commented documents can be sent and shared with other users anywhere in the world. Accessibility to files gets much more manageable with such features.
  • You can avoid unnecessary rejections of the document that you must submit to the higher authorities. The option of commenting would not disrupt the formatting of the PDF file, helping you to amend all the problems in the document without going to any other source.


Many students or individuals don't know how to add comments in PDF files which may prevent them from smart learning. By adding comments or annotations, you can highlight the important text or can add essential details related to the text in the comment box.

To improve your reading comprehension in PDF files, read this article to get the ultimate help. That is UPDF which can help you to open, view, and edit PDFs. If you want to know more about other tools to insert comments in PDF, here are the best 10 PDF annotators on market, giving you more choices to choose the right tool to annotate your PDF.

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