Top 10 PDF Annotators in 2024 - Best in the World

Ever tried to annotate a PDF file? You probably know how difficult and time-consuming it can be. It can be worse when you use an unsuitable PDF annotator. To help you out, we tested many PDF annotators on the market and picked up the best 10 ones according to features, pros, cons, affordable price, and more.

Here, we list these 10 tools with their features, pros, and cons so that you can pick up the one you need.

Part 1. Top 10 Free & Paid PDF Annotator

1. UPDF - The Best PDF Annotator

UPDF is a robust PDF annotator. This PDF annotating tool supports adding highlights, underlines, strikeouts, sticky notes, text boxes, stamps, stickers, and different shapes in PDF for annotation. If you want to annotate with your style, you can also do that with the pencil which allows you to draw on PDF. It has a user-friendly interface and easy navigation that is specially designed for the ease of its users. Apart from annotating features, UPDF allows you to edit, convert, OCR, protect, and organize PDF pages effortlessly. What's more, its UPDF AI may surprise you as it can help you summarize, explain, translate, chat for PDF, and more. Want to test all features, download the free trial via the below button now. And want to know more features about UPDF, you can read this review of UPDF from TechAdvisor.

Pros:

• It has all kinds of robust PDF annotation tools, including text boxes, highlights, squiggly, pencils, sticky notes, etc. It has more annotation tools than other PDF annotators.
• It supports 100+ beautifully designed stickers for you to use.
• All-in-one PDF software to read, annotate, edit, convert, organize, and password-protect PDF files.
• Compatible with Windows, Mac, Android, and iOS. All versions support the annotation feature.
• Time-saving tool. Blazing-fast speed to load and view PDF files.
• It remains format consistent while converting PDF documents.
• It has the advanced OCR feature to turn scanned documents into searchable and editable formats.
• Easy to use and user-friendly interface.
• You only need one premium account to use on 4 Devices (2 desktops and 2 mobiles). And now, the price is very low, you can upgrade to the pro version here.

Cons:

• The free version will add the watermark to the PDF if you want to save it after annotating the PDF.

If you are interested in watching the video on how to annotate a PDF, here is the video for you.

If you want to learn more about PDF annotation apps for Mac, we've also listed 5 easy-to-use PDF annotators on Mac for you. You can check them if needed.

2. Adobe Acrobat Reader - Free PDF Annotator with Limited Features

Adobe Acrobat Reader is a standard PDF annotation tool to annotate, comment, print, and sign e-forms. It is free and easy to download and install. It has a variety of annotation tools present in it. It allows you to sign, collaborate on, and annotate PDF files easily. However, this free PDF annotator only has basic features. It doesn't have many advanced features, such as you can't edit PDFs, convert PDFs, or OCR PDFs.

Pros:

• Compatible with all devices
• Ability to zoom & customize the toolbar
• Hassle-free e-sign
• Password protect PDF files
• Easy to navigate
• Free to use the annotation features.

Cons:

• The top features are only available for the paid version.
• The paid version is very expensive.
• The interface is not beginner-friendly.

3. PDF Annotator

PDF Annotator is a standalone tool for all your PDF purposes. It allows you to add notes, annotations, and drawings to any PDF document. You can easily add comments on the top of the PDF page with this annotation app for Windows. Its feature to restore the original document with one click makes it stand out. 

Pros:

• You can easily add images.
• Add stamps from several virtually available options
• Available for an easy-to-use layout
• Group and lock annotation
• Can save annotations in the original file
• A user-friendly software 

Cons:

• Digital signatures are not supported
• Windows-only annotation software
• It is not well known.

4. Foxit PDF Annotation Tool

Foxit PDF is also one of the best annotation and PDF editor tools that includes a typewriter tool, note highlighter, pencil, and much more. You can easily edit PDFs from anywhere – desktop, or mobile. It is a lightweight system that provides multiple annotation options. 

Pros:

• Embedded social media sharing
• Support Windows and Mac
• Easy-to-use interface 
• Advanced text editing

Cons:

• It does not allow multiple devices per license
• It is not a free annotation tool
• It is a little hard to find the tools you want if you are a beginner

Comparing Foxit and UPDF, you will find that Foxit doesn't have the sticker options in the annotation tools. It also doesn't have the slideshow feature but at a much more expensive price. That's why you suggest you choose UPDF and download it now by clicking the button below:

5. Nitro PDF Annotator

Nitro PDF Pro is software to annotate PDF files. It comes loaded with several various features. You can combine, annotate, comment, and edit PDF documents. It also allows you to condense the collection of documents into single, searchable documents. The team collaboration feature lets you easily view, share, annotate, and collaborate on documents. It has a familiar Microsoft Office-style interface for easy adaptation.

Pros:

• Easy-to-use signing tools
• Batch security
• Scan and OCR PDF files
• An affordable option as compared to others
• Regular updates

Cons:

• Limited functionality in free mode
• It doesn't include advanced annotation tools
• You have to purchase it twice if you want to use it on both Windows and Mac

6. SwifDoo PDF Annotator

SwifDoo PDF is an all-in-one PDF annotator software. It is lightweight software that enables you to create, convert, merge compress, and sign PDF documents. It allows you to view and annotate quickly even for heavy files of 600 pages. It has a Microsoft Word-like user interface which makes it easy to use. It also enables you to easily insert or replace images in a PDF file if necessary.  

Pros:

• Free trial option included
• User-friendly interface
• No data loss
• Functions instantly between PDF documents
• Option to secure documents available

Cons:

• Windows-only annotation tool
• Not famous and few people know about it

7. Soda PDF Annotator

Soda PDF is a PDF annotator software built with other PDF tools to make your life simple. It offers PDF editing tools that work across multiple devices. You can edit, merge, converge, convert, or split PDF documents easily with Soda PDF. Download it to use as a desktop app or use it online from your web browser. Its other features include adding sticker notes, OCR, e-signatures, and much more. However, there aren't enough annotation tools available.

Pros:

• Supported by Windows and Mac
• Fastest Microsoft to PDF converter 
• Supports 8 languages
• Available online & offline 
• Involves third-party cloud apps
• Supports batch processing

Cons: 

• The Trial version needs registration
• Some bugs reported in the latest version
• Online tools are available with fewer customization options
• There are fewer annotation tools available

8. PDF-XChange Editor

PDF-Xchange Editor is a fully-featured PDF annotator tool. It helps you to edit, correct, add, or remove text effortlessly. Its free version allows you to use several features which include creating, modifying, and highlighting PDFs. It has a track change feature that allows you to track all the changes done to a PDF file. You can also move, resize, or remove graphics using this PDF annotator tool.

Pros: 

• Free & paid versions are available
• Improved image embedding
• Quick text manipulation
• Track change function available 

Cons:

• Windows-only annotation software
• The free version has many limitations
• The interface is outdated and a little complicated

9. PDFescape - Free Software to Annotate PDF

PDFescape is a free PDF annotator software that allows you to comment and markup PDF documents. It is an online open-source PDF reader and editor. You can easily highlight, underline, and strikethrough content with the PDFescape editor. It enables you to choose from a number of various features available online and offline.

Pros: 

• Available for online & offline use
• No watermarks
• Simple & easy to use interface
• Form-filling options are available
• Share documents online

Cons:

• The free version's features are limited
• Only supports Windows 
  

10. Qiqqa - Annotator for Windows

Qiqqa is a free research and reference manager used by academics, researchers, and businesses. It is an open-source platform that lets you automatically produce citations and bibliographies in various styles. Add annotations, highlights, and free-form drawings, or view multiple pages at once with Qiqqa. It provides superb reference and document management. You can import documents into separate libraries and do much more. 

Pros: 

• Google-like power
• Provides unlimited storage 
• Android app available 
• Protected & secure PDFs

Cons:

• Windows only software
• No other advanced PDF-related features

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Part 2. Comparison among the 10 PDF Annotators

After introducing the top 10 PDF annotators above, do you know which one should you use? If not, you can check this comparison chart.

From the below comparison, you will see that as the most cost-effective option, you just need to purchase UPDF once and use it for all platforms. Unlike Acrobat and Foxit, UPDF is very easy to use and the user interface is intuitive. You can read, annotate, convert, protect, organize, and OCR PDF files. Download it now by simply clicking the button below:

Tool	Pricing	Compatibility	Easy to Use	Overall Rating
1. UPDF	US$35.99/Yr US$35.99/Perpetual (One purchase, all platforms)	Windows Mac iOS Android		5
2. Adobe Acrobat	Pro: US$179.88/Yr Standard: US$155.88/Yr	Windows Mac iOS Android Web		5
3. PDF Annotator	US$119.99/Yr	Windows		3
4. Foxit PDF Editor	From US$79/Yr to US$300/Yr	Windows Mac iOS Android Web		4
5. Nitro Pro	Windows: US$143.99/one-time Mac: US$179.99/one-time	Windows Mac		4
6. SwifDoo PDF	US$20/Mo US$69/Yr US$159/Perpetual	Windows		3
7. Soda PDF	360: US$99/Yr Business: US200/Yr	Windows Linux Web		3
8. PDF-Xchange	Editor: US$56/Yr PLUS: US$72/Yr Pro: US$121/Yr	Windows		3
9. PDFescape	Premium: US$35.88/Yr Ultimate: US$71.88/Yr	Windows Web		3
10. Qiqqa	US$119.99/Yr	Windows		3

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Part 3. FAQs on Choosing a PDF Annotator

Q1. Are PDF annotators free?

There are free PDF annotators as well as paid ones available. There are many differences between free and paid tools. Basic annotation tools such as Highlight will be available in free PDF annotators, however, if you are looking for robust tools, you can choose a paid one, which will offer much more options for markup. Take UPDF for an example, it offers highlight, underline, strikethrough, and squirrely line tools to markup texts, it also provides sticky notes, text boxes, typewriters, text callouts, stamps, stickers, signatures, shapes, pencils, and erasers. Amazing, right? You can try it now.

Q2. What is the best software to annotate PDFs?

Personally, I think Adobe Acrobat Pro DC and UPDF are the best software to annotate PDFs. The reasons are that these two powerful tools provide the most powerful ability to annotate your PDF files. And considering the price difference, (Adobe Acrobat is US$239.88 per year, and UPDF is US$29.99 per year) I would choose UPDF.

Q3. What is a PDF Annotator used for?

A PDF annotator is used to emphasize some content on your file, add comments, and review the document to collaborate with others. It is widely used by students, teachers, lawyers, realtors, and anyone who uses the PDF format.

Q4. How do I choose a PDF Annotator?

To choose a PDF annotator, you should consider the following aspects:

• Is the price reasonable?
• Are the annotation tools rich and useful?
• Is the software stable when performing tasks?
• Is the running speed fast?
• Do I need advanced features other than the annotation feature?

It is clear that UPDF would be the best choice as it provides the richest tools at the lowest price, and the loading speed is very fast.

Wrapping up

PDF annotators have made our lives much easier. They not only improve productivity at work but also allow you to collaborate seamlessly with users with the tools provided. Annotate, highlight, convert, add stamps, or collaborate with users with one of the PDF annotator tools mentioned above.

Each tool allows you to work effortlessly and has its own significance but if you ask my favorite PDF annotator, I would recommend UPDF PDF Annotator. It can be used both at work and at home and provides a variety of features to work through. You can download UPDF via the below button to check all features.