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Top 5 Open Source PDF Readers in 2023

Personal or business, work-wise PDF files are the most popular formats where most people find it easier to manage and transfer. Viewing and sharing PDFs has now been made simple thanks to loads of PDF software that are developed just for the job and are made available to be utilized on your desktops. Using an open source PDF reader is an excellent way to view PDF files. At the end of the article, there is also a comparison of the 5 open source PDF readers.

Top 5 Best Open Source PDF Readers

1.  UPDF

At the helm of this list of great PDFs, the software is undoubtedly the best open-source PDF reader you should have, UPDF for Windows and Mac. This software is placed ahead of the other PDF readers, and the reason is that UPDF has its own unique way to get the job done while only requiring a few clicks to start working with your PDF files. PDF reading can now be done in the easiest manner in a very friendly application - UPDF.

Delightful Reading Experience

  • It has multiple page display modes for you to read PDF files, like single page view, single page scrolling, two page view, and two page scrolling.
  • The slideshow feature enables you to display a PDF document as a slideshow.
  • It offers the dark mode feature to give you the best reading experience.
  • You can create and add bookmarks in PDF easily.
open source pdf reader updf

Edit PDF Smoothly

You can do more than just read PDF files with UPDF. It also has advanced editing tools for making changes to your PDF's contents. All the texts, images, and links are editable with UPDF. It doesn't take long to get started with this program in order to achieve those high-quality changes to your PDF files, and it immediately offers you all of the capabilities you need.

open source pdf viewer updf

Annotate, Convert, OCR, and Organize PDF Pages

Other functions include text highlighting, underlining, strikeouts, and noting texts, as well as removing, adding, and rotating the pages of a PDF file. You'll also love its OCR feature which is very smart for including those images found on your PDFs to convert to editable texts.
As versatile as it may seem with all these handy features you can do, the UPDF is a reliable open-source reader which will have improved features for you to have such as a smart collaborative feature, very light and compact file size, and all-in-one capability.

open source pdf reader for windows updf



  • Very user-friendly and elegant interface.
  • Super experience with PDF editing.
  • Supports Windows, Mac, iOS, and Android systems. Versatile to use for reading PDF files.

2. Adobe Reader Open Source

Next in line is the software furnished by the same company that started it all for PDF files- Adobe. The Adobe Acrobat Reader is also an open-source PDF viewer you can have if you are for those very advanced gizmos and tools to do more than just view your PDF files but also edit them and apply the changes you desire.

Different reading modes, text highlighting, making notes, filling forms, digital signatures, adding stamps, and other features are only among the best you can have with Adobe Reader open source surely useful for most users' PDF file management experience.

This Adobe program also offers a tabbed design that allows you to open several PDF files at once. It's also the best PDF reader for processing large files that other lightweight programs can't handle, but it costs US$14.99 per month. So you can also learn some Adobe reader alternatives if needed.


  • Supports sync with other adobe platforms
  • High-quality conversions to multiple formats
  • Advanced editing


  • Not beginner-friendly
  • Price is expensive
adobe reader open source

3. Foxit Reader Open Source

The next significant item to attempt to improve your PDF reading experience is Foxit Reader, which is a well-known name in the world of document readers, similar to Adobe Acrobat Reader DC, although Foxit is far lighter than Adobe's PDF reader. Not long ago, Foxit also revealed its new online ConnectedPDF Document Management System. Its Text Viewer option removes the file's sophisticated formatting and exposes it in a Notepad-like manner. Collaboration capabilities improve your PDF experience even further by allowing you to work online and share your PDF with others.

The complete edition of Foxit Reader open source is a tool for viewing PDF files as well as organizing large amounts of information for enjoyable work, and it can be purchased for US$129/year.


  • Cloud-based tools are integrated.
  • Can work simultaneously or collaboratively.
  • Specifically created for high-quality editing and printing.


  • You may be forced to buy the licensed version to access full features.
  • Not space-wise(takes up many system processes).
  • Expensive.
foxit reader open source

4. LibreOffice

For all operating systems, especially Windows, LibreOffice is one of the most remarkable open-source PDF readers you can have. You can modify words and photos, as well as whiteout and type on top of the text you wish to redact.

In the field of PDF viewing, LibreOffice is a formidable contender. It's an excellent alternative for those who are unable to utilize proprietary software. It comes with all of the functionality you'd expect from a good open-source PDF editor.

LibreOffice is a popular alternative to Microsoft Office, despite its inconsistency in terms of the user interface. Although it is a powerful word processor, it struggles to edit PDF files. However, it will allow you to perform rudimentary editing.


  • It can open PDF documents.


  • Limited editing feature.
  • May not be ideal for large PDF files.
open source pdf reader for windows libreoffice

5. Google PDF Reader

To clinch the list of open-source PDF viewers for Windows, you certainly would not want to miss is the Google Chrome browser. It is another open-source PDF reader that can open PDFs without any extension. You will have no trouble using this program as long as your browser is up and running, allowing you to read PDF files downloaded in a lightweight and quick manner.

You may use this free software to read PDF, DOC, XLS, and PPT files directly in your web browser because it only works on a local level, bypassing the server. You do not need to install any other software in order to begin reading PDF files. The files or PDFs you submit are not kept or shared, but they can be viewed using cloud-based services.

However, this tool doesn't have any advanced features, such as annotating PDFs, converting PDFs, and OCR. So if you want to work with PDF documents easily, you should choose UPDF to help you.


  • Easily accessible to most users.


  • Cannot have all of the essential functions, such as modifying the PDF itself.
  • It's not a standalone program, but rather a browser extension.
best open source pdf reader google pdf reader

Comparing the Top 5 Open Source PDF Readers

There are many open-source PDF readers available; however, finding out the best reader is important. The following table highlights the top 5 open source PDF readers available, with a definitive explanation of features, and you will find UPDF is the best one of these five.

ToolOperating SystemPricingRatingSpeedFeatures
UPDFWindows, Mac, Android, iOSFree for the reading feature.
(Start from US$39.99/yr for advanced features like OCR)
4.8/5FastRead PDF
Annotate PDF
Convert PDF
Password-protect PDF
Organize PDF
Adobe Acrobat ReaderWindows
Mac, Android, iOS
Monthly: US$29.99/month Annual: US$239.88/year4.4/5FastNeed to Buy Tool for Advanced Functions
Foxit ReaderWindows, Mac, Android, iOS, Linux, CitrixFree for the reading feature.
(US$149/Yr for the editing feature)

4.3/5MediumOffers Basic PDF Viewing Feature
LibreOfficeWindows, Mac, LinuxFree for the reading feature.4.0/5SlowIt is an Office suite that can view PDF files, but it is not professional PDF software.
Google PDF ReaderWindows, Mac, Linux, Android, iOSFree for the reading feature.3.5/5FastNo Particular Editing Features are Available

With the provided details, it can be seen that UPDF offers the best speed with a diversity of features. As we compare with the rest of the PDF readers, it is evident that most of them lack in some major departments. UPDF gives the best features in terms of its open-source system, for it is both efficient and adaptive.

FAQs about Open Source PDF Reader

What is Open Source?

Open source is source code that is made freely accessible. That is to say, anyone can view, edit, and distribute the code. It is a decentralized software development and is developed in a collaborative way. So most of the open-source software is free to use.

What is the Best Open Source PDF Reader?

UPDF is the best open-source PDF reader because of its rich features, delightful reading experience, blazing speed, attractive interface, stable performance, and multiple platforms.

What is the Best Alternative to Adobe PDF Reader?

There is no doubt that UPDF is the best alternative to Adobe PDF reader. With UPDF, you can easily view, annotate, edit, convert, protect, compress, split, and crop PDF files. What's more, users purchase one and will get UPDF on all platforms. That's very convenient if you need to view PDF files on different platforms.


As you may have read these PDF readers, there are a lot of key points to observe when it comes to choosing the finest open-source PDF reader for you. Given the amount of work that must be done with these tools, you'd better choose an offline PDF reader like UPDF, as it has a greater degree of control over the variety of features than online editors so be also sure to include it as a standard.

There are a variety of free PDF readers available on the market; however, if you're seeking a better solution to excellent PDF reading that really has it all, the UPDF is the way to go. You will know that a UPDF is the best pick for you, capable of doing more than just reading a PDF document. Designed with an elegant interface with only a few quick steps to do the work for you, UPDF is constantly providing you with benefits that are worthwhile in the long run.