How to Annotate a PDF File for Free 2023

How to annotate a PDF file for free? Marking up a PDF document will enhance memory and improve work efficiency to a large extent. However, many PDF editors lock the PDF annotating features to free account users. It is not that easy to find solutions to annotate PDFs for free. In this article, we summarize free PDF editors to add annotations in PDF after testing numerous PDF editing software. Each of them is simple and convenient to use! For Windows users, WorkinTool PDF Converter is the top option. It has:
🤩 A long free trial to annotate PDFs
😘 Easy-to-navigate user interface
👑 Stable PDF importing and downloading speed
✨ High user privacy guarantee

Last updated on Mar 21, 2023 by Betty Written by Eleanor
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How to Annotate a PDF File for Free 2023

Annotating is a highly efficient solution to help us supplement ideas and organize essential information. Adding PDF annotations such as text notes, highlights, signatures, images, shapes, and stamps will enhance memory, facilitate collaboration, and improve productivity. How do you annotate a PDF? Well, annotating PDFs is not rocket science. This article will share how to annotate a PDF file for free on Windows and Mac. Besides, some frequently asked questions are answered. It is believed that you’ll find what you need in this article after reading it.


🌟 How to Annotate a PDF Document on Windows

Finding a free, reliable, and powerful PDF editor takes effort. But today, you are in the right place! We sincerely recommend a FREE PDF reader and editor to you—WorkinTool PDF Converter. As the name shows, it is software with all-in-one features.  It not only works as a PDF reader and editor but also is endowed with practical converting features. It can convert PDFs to and from any format, including Word, PPT, Excel, Image, and HTML.

As a PDF editor, it allows you to annotate PDF files with text, notes, signatures, images, stamps, shapes, and highlights. All the tools in PDF Edit and PDF Reader are free to use without size limits. However, if you use other feature, you can only select each file within 2MB in free version. Coming back to the detailed guide, let’s look at how to mark up a PDF with WorkinTool PDF Converter together. Assuming you’ve downloaded this software and gone to “PDF Edit,

workintool pdf converter download icon

1 Add sticky notes

To add sticky notes to PDF files, you should first find the “Note” icon on the upper toolbar. Then change the note style (fill color and note icon); five colors are available, and thirteen icons are for different use. After selecting, click on the page where you want to add a note and type in what you want to say to the note box.

add note to pdf

2 Insert images and stamps

To insert an image into a PDF document, find the “Image” icon on the toolbar and click it. Then choose an image on your PC to upload and put it anywhere on one of the PDF pages. You can change the image transparency, add notes to pictures, and drag the frame to resize the picture in this feature.

insert images

You can also click “Stamp” in the dropdown menu to add stamps to PDF for free. WorkinTool provides some free existing stamp designs. If you don’t like it, it also allows you to custom stamps. To customize a stamp, you need to type in the stamp text first, choose whether to show the date and time (auto recognition), select as you like and click “Create Stamp.” After creation, adjust its size and location to make it fit on the PDF page.

insert stamps

3 Add text annotations

You can type on a PDF document by clicking on the “Text” icon. It allows you to change text color, fill color, and transparency. More styles like text font, size, and alignment are available. After settings, select the area where you want the text to show.

add text to pdf

4 Sign a PDF document

You can sign a PDF without printing or scanning. With the “Signature” feature in WorkinTool, you can sign a Portable Document Format online with different colors. Once you add a signature to a PDF document, it will be stored in the cloud, convenient for your next use.

sign a pdf

5 Draw annotations on a PDF

Tap on “Drawing,” You can select different tools to draw on the PDF. This editor has a free-form drawing brush, a free-form highlighter, and a text highlighter. Click the one you like, and a setting panel will appear, enabling you to configure brush color, fill color, opacity, brush thickness, and blend mode.

draw on pdf


  • In addition to the above annotation, WorkinTool PDF Converter also entitles users to PDF encryption, compressing, merging, splitting, etc. And these are just the tip of the iceberg. You’ll find more surprises when you put it into practical use.

How to Annotate a PDF Document on Mac

If you are using macOS, it is easy to mark up a PDF file in Preview, a built-in Mac feature. Therefore, you don’t need to download a third-party tool. Now let’s look at how to annotate a PDF file in Preview on Mac for free.

  • 1. Firstly, click on “Show Markup Toolbar” in the dropdown menu of “View,” or press the icon on the top right.
  • 2. Secondly, choose tools to mark up the PDF file. (Preview allows you to type text, create signatures, draw shapes, and add notes and highlights to PDFs.)
  • 3. Finally, click “Done” to save the annotations in PDF.

annotate a pdf in preview on mac


How to Annotate a PDF Online for Free

WorkinTool PDF Converter also has its online version; if you want to know how to mark up a PDF without desktop software, head to WorkinTool PDF editor online. The interface and operation steps of the online version are similar to that of the desktop one. It is compatible with all systems. All you need is just a stable network connection. Check out how to annotate a PDF online for free with it:

  • 1. Open the online WorkinTool PDF Editor page.
  • 2. Upload your PDF and annotate it with the provided tools on the top menu bar.
  • 3. Press Download to export the annotated PDF file.

workintool online pdf editor

FAQs on How to Annotate on a PDF

🧐 Can I annotate a PDF for free?

Yes, you can. With the free PDF editors mentioned above, you will know how to mark up a PDF without Adobe Acrobat or Adobe Reader, whether you are a Windows or Mac user.

🧐 How do I annotate a PDF in Chrome?

Try to annotate a PDF in Google Drive in Google Chrome. You can do it through Google Docs or other online PDF editors. As a note, Google Drive only has up to 15 GB of storage, which is quick to run out. Also, opening PDF files with Google Docs may lose the original formatting. In addition, other online PDF editors that can connect to Google Drive usually lock their premium features to free plan users.


In this article, we talked about how to annotate a PDF on Windows, Mac, and online. This article can answer your questions about PDF annotating/markup. Hope you can find the best way to annotate PDFs.


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