Open source pdf reader windows

Aren’t we supposed to be living in a paperless world by now?

I can’t be the only person who imagined the office of the future, free from the confines of the eight and a half by eleven sheet (or A4, for my international friends), would have long since arrived. Instead, we’ve managed to land in an intermediate state of not paperless, but less paper.

It could be worse.

Between a trusty scanner, email and various other communication tools, and getting really good at organizing my digital archives, I’m not totally unhappy with where we are today. And I do occasionally admit to reading a paper book, sending a postcard, or (gasp) printing something off to give to someone else.

Until the world moves a little further from paper, print-ready file formats will continue to permeate our digital landscape as well. And, love it or hate it, PDF, the «portable document format,» seems to be the go-to format for creating and sharing print-ready files, as well as archiving files that originated as print.

For years, the only name in the game for working with PDF documents was Adobe Acrobat, whether in the form of their free reader edition or one of their paid editions for PDF creation and editing. But today, there are numerous open source PDF applications which have chipped away at this market dominance. And for Linux users like me, a proprietary application that only runs on Windows or Mac isn’t an option anyway.

Since PDF files are used in so many different situations for so many different kinds of purposes, you may need to shop around to find the open source alternative to Adobe Acrobat that meets your exact needs. Here are some tools I enjoy.

Reading PDFs

For reading PDFs, these days many people get by without having to use an external application at all. Both Firefox and Chromium, the open source version of Google’s Chrome browser, come bundled with in-browser PDF readers, so an external plugin is no longer necessary for most users.

For downloaded files, users of GNOME-based Linux distributions have Evince (or Atril on the GNOME 2 fork, MATE), a powerful PDF reader that handles most documents quickly and with ease. Evince has a Windows port as well, although Windows users may also want to check out the GPLv3-licensed SumatraPDF as an alternative. KDE’s Okular serves as the PDF reader for the Plasma Desktop. All of these have the ability to complete PDF forms, view and make comments, search for text, select text, and so on.

For a generic, simple, and fast PDF reader, try xpdf.

Creating PDFs

Personally, LibreOffice’s export functionality ends up being the source of 95% of the PDFs I create that weren’t built for me by a web application. Scribus, Inkscape, and GIMP all support native PDF export, too, so no matter what kind of document you need to make — a complex layout, formatted text, vector or raster image, or some combination — there’s an open source application that meets your needs.

For practically every other application, the CUPS printing system does an excellent job of outputting documents as PDF, because printers and PDFs both rely on PostScript to represent data on page (whether the page is digital or physical).

If you don’t need fancy graphical interfaces, you can also generate PDFs through plain text with a few handy terminal commands. Everyone has their favourite, but probably the most popular is Pandoc, which takes nearly any format of document and translates it to nearly any other format. Its ability to translate text formats is staggering, so it’s probably all you really need. However, there are several other solutions, including Docbook, Sphinx, and LaTeX.

Editing PDFs

Editing is a loaded term. For some people, editing a PDF means changing a few words or a swapping out an old image for a new one, while for others it means altering metadata such as bookmarks, and for still others it means manipulating page order or adjusting print resolution. The authoritative answer nobody ever wants is: don’t edit PDFs, edit the source and then export a new PDF. That’s not always possible, though, and luckily there are some great tools to make all manner of edits possible.

LibreOffice Draw does a fantastic job of editing PDF files, giving you full access to the text and images. There are caveats to this, because of the flexibility of the PDF format. If you haven’t installed the fonts used in the PDF, then the flow of text could change due to font substitution,. If the PDF was created from a scan, then you’ll only have images of text and not editable text.

Inkscape, too, does a good job with opening documents created elsewhere, and may be a more intuitive choice if your document is heavy on graphics. If you don’t have a font installed, Inkscape (through the Poppler renderer) can trace characters so that the appearance of text is maintained even without the actual font data. Of course, that loses the text data (you have only the shapes of letters, not the selectable text itself) but it’s a nice feature when appearance matters most.

There are standalone tools as well, like the GPLv2 licensed PDFedit, but I’ve had such good luck with Inkscape and LibreOffice that I haven’t had to use a separate editor in recent years.

If your editing tasks are less about the content and more about presentation, you might find the pdftk-java (PDF ToolKit) command useful. It can extract and inject bookmark metadata, rearrange and concatenate pages, combine many PDFs into one, break a PDF apart, and much more. If you’re not comfortable in a terminal yet, PDFSam has many similar functions, but includes a graphical interface.

Finally, you can adjust PostScript properties directly with the GhostScript command, gs. GhostScript is an open source interpreter for the PostScript, so you can perform very low-level tasks with it, such as swapping one font for another, or adjusting the resolution of images, or dropping images entirely.

Being terminal-based, these are great tools for automated manipulation, too.

We know these aren’t the only choices in town. Do you work with a lot of PDFs? Have a favorite application to help you along the way? Let us know in the comments below what you use and why it works for you.

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Editor’s note: This article was originally published in 2016 and has been updated.

This work is licensed under a Creative Commons Attribution-Share Alike 4.0 International License.

No need to spend much time testing or researching tons of PDF reading applications. Go through the 5 PDF readers that are open-source and easy to use. You will learn about these open-source PDF readers’ interface, features, and more details.

1. Sumatra PDF

Sumatra PDF is one of the best open-source PDF readers with its fast file loading speed. If you don’t need to do much editing work on PDF files, this software is a stellar option. It supports opening multiple PDF files in different tabs within one window. You can choose to show bookmarks and annotations for quick navigation. There are Single Page, Facing, Presentation, Fullscreen, and more reading modes available. This open-source PDF reader is for Windows.

Картинка с сайта: www.swifdoo.com

A distinct function of the software is that it allows you to search and find a specific word in a PDF. Moreover, it offers basic PDF annotating tools so you can highlight or strike out text, add notes, text, stamps, etc. Editing the added annotations is simple later in the open-source PDF reader. The free reader app also supports other document types, such as eBook EPUB and MOBI format, XPS, and images. It displays the files opened before in the home interface.

2. Okular

Okular is a multi-platform open-source PDF reader for Windows and Linux. The reading app packed all its annotation tools into a user-friendly graphical user interface. It is designed with a thumbnail panel, bookmarks panel, and annotations panel to improve the reading experience. If you don’t want to read the entire pages in a PDF, it allows you to trim the margins or trim pages to the selected area.

Картинка с сайта: www.swifdoo.com

A good thing about the free open-source PDF reader is the digitally signing feature. This feature is not offered in many other PDF software. Besides PDF documents, the program allows you to read EPub books, images, Markdown documents, and more file types. It has the option to convert PDF to TXT plain text format.

3. Inkscape

Inkscape is a top PDF reader that is free, open source, and cross-platform. The open-source PDF reader is available for free download on Windows, Mac and Linux. The best part about it is the PDF editing ability. Nearly no open-source software can change existing text in a PDF but it can. Moreover, it enables you to draw lines and shapes and type text on PDFs as you prefer. You can also remove and add images and links in your PDF file.

Картинка с сайта: www.swifdoo.com

Inkscape is an open-source PDF reader, writer and editor, and you can split, create PDFs, and do a lot more with it. One thing to note here is that the app only lets you edit a single PDF page at a time. You need to open each page of your PDF in separate windows to edit more pages. More than a PDF viewer and editor, Inkscape is also a quality vector graphics creating and editing software.

4. XpdfReader

If you are looking for the best free and open-source PDF reader, take a look at XpdfReader. This is a lightweight and speedy PDF viewer and toolkit that can run on Linux, Windows and Mac operating systems. It provides panels on the left side for instantly viewing layered content and bookmarks in a PDF. To open and read a PDF file, go to “File” to choose “Open”, and select the PDF to import into the reader program, then apply your desired reading option to start reading.

Картинка с сайта: www.swifdoo.com

The outstanding part of XpdfReader lies in its set of utilities called Xpdftools. You can add Xpdftools from the open-source PDF reader’s site and use them to perform advanced tasks. These tools are command-line tools for users to convert PDFs to images or text, extract images and do many more.

5. Evince Document Viewer

Like most other PDF programs, Evince Document Viewer is another open-source PDF reader with a highlighter included. It allows you to search for and highlight text in a PDF document and add text annotations. You can optionally expand the thumbnail panel in the left sidebar of the software to make page navigation effortless. While reading a PDF, the Linux-based open-source PDF reader app allows you to show PDF pages side by side or in a slide-show view.

Картинка с сайта: www.swifdoo.com

Evince can display a multi-page or single-page PDF document for you to read. The reading app is a universal document reader specifically for Gnome users. It supports a wide range of different types of documents, including PDF, Postscript, djvu, tiff, XPS, and comic books.

The Best Alternative to Open Source PDF Reader

The aforementioned open-source PDF readers and viewers take the effort out of purchasing commercial software to view and make basic edits to your files. But what if your need is more than just annotating and reading?

For example, you may wish to change the existing text, rearrange the pages, convert the file format or do something that these programs cannot help. In that case, set your sights on SwifDoo PDF, which is one of the best alternatives to Adobe Acrobat. It has nearly all the PDF tools on the market but is super budget-friendly.

Картинка с сайта: www.swifdoo.com

It’s safe to say that no open-source software can work most or all the same as commercial software. But you can expect a cost-effective application. SwifDoo PDF is your best alternative to an open-source PDF reader with PDF editing, converting, page organizing, powerful OCR, and more tools. It’s affordable for an individual and a free PDF reader. Browse its key features below:

• Add, delete, and change text, images, and other objects in a PDF.
• Create PDF files, and convert PDFs to Word, Excel, TXT, image, and various different formats and vice versa.
• Make annotations and white out on PDFs.
• Merge, split, compress, read aloud, and translate PDF files.
• Insert, delete, replace, extract, and rotate PDF pages.
• Add or remove watermark from PDFs.

Conclusion

Among all the 5 open source PDF readers, Inkscape is the only one acting as a free PDF editor. It is capable of making a PDF editable. In terms of the best PDF reader that is developed to be open source and downloaded with a more modern interface, it is Okular.

Open-source software programs have limited functions. To strike a balance between complicated features and software cost, try SwifDoo PDF for 7 days without limitations.

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FAQs

Q: Which PDF maker is free open source?

A: To create or make PDF documents, you can use these free and open-source PDF readers and makers: LibreOffice Writer, OpenOffice Writer, Scribus, and Inkscape. They allow you to create PDFs from already opened files and write documents to export in PDF format.

Q: What is an open-source alternative to Adobe Reader?

A: Adobe Reader is a free PDF reader with comment tools and a digital signing feature. Okular is a good open-source alternative to Adobe Acrobat with the same ability to open, comment and sign PDFs.

Q: What is the best free PDF reader?

A: The open-source PDF readers Sumatra PDF and Okular are two of the best and they are free. In addition, there are some non-open source best free PDF readers, such as SwifDoo PDF. They are also easy to use and serve users with excellent reading experience as well as free features.

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Помимо программ от Adobe есть много альтернативных специализированных библиотек и утилит для работы с PDF. Что характерно, зачастую опенсорсные инструменты даже удобнее, чем официальный* софт. Альтернативные ридеры/редакторы по функциональности сильно отличаются от Adobe. В свою очередь, программы Adobe сами отличаются от официальных спецификаций PDF.

*Примечание: программы Adobe не «официальные» в прямом смысле слова, потому что PDF является открытым и бесплатным стандартом ИСО.

Налицо как минимум три класса множеств:

1. функции из спецификаций PDF разных версий (самые большие множества);
2. функции «официальных» Adobe Acrobat/Acrobat Pro/Reader (ещё несколько множеств);
3. функции альтернативных ридеров, утилит и библиотек для обработки PDF.

В 2017–2023 гг должно завершиться принятие пакета стандартов PDF 2.0, который пришёл на смену прежним версиям PDF 1.0–1.7. Он требует реализации новых функций при сохранении обратной совместимости. Крайне сложная задача.

На практике иногда удобнее использовать легковесные инструменты от сторонних разработчиков, которые поддерживают лишь часть спецификаций PDF, но только нужные вещи, без груза легаси. Среди них специализированные утилиты, которые выполняют одну задачу, но лучше, чем коммерческие инструменты.

Библиотека для генерации PDF

В качестве конкретного примера можно взглянуть на маленькую библиотеку CapyPDF от Юсси Пакканена (Jussi Pakkanen). Это библиотека для генерации PDF, в ней реализована малая часть стандарта, а некоторые функции реализованы, но не открыты для использования. Например, в текущем рендеринге PDF функционирует следующее:

• Основные графические команды для RGB, градаций серого и CMYK
• Поддержка ICC-профилей
• Загрузка изображений PNG, JPG и TIFF (включая CMYK TIFF)
• Вставка файлов JPG напрямую без предварительной распаковки
• Использование изображений в качестве маски для рисования
• Работа со встроенными в изображения цветовыми профилями
• Использование встроенных шрифтов PDF
• Использование шрифтов TrueType, в том числе с возможностью усечения подмножества шрифтов (font subsetting)
• Все операторы шрифтов PDF, такие как дополнительная подложка (extra padding), верхний/нижний регистр и установка в качестве обтравочного контура (clipping path)
• Переходы между страницами

Реализовано, но не открыто (код есть, но не добавлен или оформлен в виде комментариев):

• Дерево навигации по документу
• Оверпринт (наложение одного цветного элемента на другой без создания выворотки)
• Структура и аннотации
• Дополнительные цветовые каналы (в спецификации PDF они называются сепарациями)
• Объекты XObjects для форм
• Встраивание файлов
• Аннотации (только несколько типов)
• Поддержка цветового пространства L*a*b*
• Цвета ICC в примитивных операциях заливки
• Оттенки Type 2, 3 и 4 (например, градиенты)
• Цветовые узоры

А есть ещё функции, которые не совсем совпадают со спецификациями. Скажем, навигация внутри страниц. Согласно спецификациям PDF 2.0, раздел 12.4.4.2, на одной странице можно реализовать много пунктов, которые будут открываться один за другим по щелчку мыши. Это сделано для презентаций. Однако почти все генераторы PDF реализуют список не на одной, а на нескольких страницах. То есть список из пяти пунктов занимает не одну, а пять страниц. Единственный ридер, который поддерживает навигацию внутри страниц — это Acrobat Reader. Но сейчас ни один генератор PDF, никакая программа для создания презентаций не экспортирует теги навигации по страницам.

Причина в размытости формулировок официальной спецификации, так что эту функцию трудно реализовать однозначным образом. Там в качестве основных операций используются опциональные контент-группы (optional content groups) и навигационные узлы. Первые поддерживаются всеми ридерами PDF, вторые — нет. Каждый навигационный узел представляет собой состояние (state). Когда пользователь перемещается вперёд и назад, ридер выполняет определённое действие, которое может быть использовано для скрытия или отображения опциональной контент-группы. Согласно спецификации, система работает по сложному двунаправленному алгоритму:

Картинка с сайта: habr.com

По мнению некоторых разработчиков, внедрение в эту схему корня (root) — излишнее усложнение. С другой стороны, такой вариант позволяет практически любой документ реализовать в виде одностраничного PDF с множеством «состояний».

Здесь сами спецификации нуждаются в исправлении, потому что некоторые части там противоречат друг другу.

Подводя итог, CapyPDF не может открыть и редактировать документы, зато справляется с одной конкретной задачей — генерация PDF — настолько, насколько это позволяют спецификации.

Движки для рендеринга PDF в браузерах

Кроме отдельных ридеров/редакторов PDF, особого внимания заслуживают браузерные движки рендеринга и веб-редакторы. Они тоже становятся всё функциональнее с каждой новой версией. Например, в Firefox с версии 106 (октябрь 2022 года) появился встроенный редактор PDF, включающий в себя добавление текста и рисование фигур, в том числе подписей:

Картинка с сайта: habr.com

Firefox позволяет делать аннотации: печатать или писать от руки прямо в PDF, выбирать цвет, размер, толщину линий, непрозрачность и т.д., а затем сохранять PDF-файл локально с новыми дополнениями.

Недавно мы рассказывали про очень удобный веб-редактор simplePDF, ориентированный на простейшие и быстрые манипуляции с PDF, как то:

• вписать имя в PDF-форму;
• проставить галочки;
• поставить подпись;
• добавить фото.

Демо:

К сожалению, онлайновые PDF-редакторы пока не поддерживают подпись документов с помощью цифровых сертификатов, защиту от редактирования и другие функции безопасности, которые реализованы на платформе Adobe PDF.

Для цифровой подписи PDF тоже можно использовать отдельные инструменты. Например, простую опенсорсную утилиту open-pdf-sign из командной строки. Подписи невидимы (по умолчанию) или явно демонстрируются:

Картинка с сайта: habr.com

Консольную утилиту можно использовать с существующими сертификатами от любых удостоверяющих центров.

Вообще, стандарт PDF 2.0 настолько сложный и объёмный, что реализовать его целиком согласно спецификациям в одной программе крайне сложно. Например, основной документ ISO 32000-2:2020 — Document management – Portable document format – Part 2: PDF 2.0 содержит 1003 страницы:

Картинка с сайта: habr.com

К нему принято ещё несколько приложений, в том числе приложение по цифровым подписям ISO/TS 32002:2022, и это только два из шести документов в пакете стандартов PDF 2.0.

В целом, иногда эффективнее использовать маленькие специализированные утилиты. Такие опенсорсные утилиты существуют отдельно для генерации, просмотра и подписи PDF.

Nowadays everyone who has to deal with electronic documents needs a PDF reader due to the popularity and widespread distribution of this format. In this article, you will find a brief overview of the best open source PDF readers so that you can choose one for your work or personal use on different platforms.

Картинка с сайта: www.onlyoffice.com

Why you need an open source PDF viewer

First of all, let’s be clear on that the phrases “PDF reader” and “PDF viewer” mean the same sort of thing and can be used as synonyms. It’s an application that allows you to open PDF files on your device and view their content. They can also be able to perform some other basic operations, like adding annotations and saving PDFs to other formats, but they don’t usually allow you to change or modify information in your files.

In many cases, a PDF reader is all you need to work with PDF files. You don’t need to install complex PDF editing tools if you just open files for viewing and save documents to PDF for printing.

In our list, you will find some of the best open source tools that you can use to view the content of PDF files. In comparison with proprietary software, open source PDF readers offer the same features but are more reliable and transparent. They are also often free of charge, which allows you to do other things with your money.

1. ONLYOFFICE PDF Editor

ONLYOFFICE PDF Editor is a very interesting option if you are looking for an open source PDF viewer and editor. It’s part of a full-featured collaborative office suite that can handle office documents of different types and PDF files.

You can use the ONLYOFFICE suite to create and edit text documents, spreadsheets, presentations and fillable forms as well as open, view and edit PDFs. The built-in viewing tool makes it possible to navigate through the pages of PDF files using a thumbnail pane with page previews.

Also, there is a navigation pane that allows you to easily access the required page of your file with a few clicks. Using the Select tool, you can copy text and graphical objects, and the Hand tool allows you to browse the entire PDF document.

The ONLYOFFICE open source PDF viewer also offers such features as downloading, printing and zoom settings. If you have to read PDFs at night, you can switch to Dark Mode.

When it comes to PDF editing, the ONLYOFFICE suite has plenty of useful features. ONLYOFFICE PDF Editor allows users to switch between the Commenting and Editing modes depending on what they want to do to their PDFs. The Editing mode enables you to edit text in your file, insert, modify and delete visual objects, such as shapes, images and tables, add, rotate and delete pages, leave text comments and callouts, and even communicate with other people in the built-in chat if they open the same document online.

Another important feature is the ability to annotate PDFs. Using ONLYOFFICE PDF Editor, you can make notes, mark up texts and draw what you need, e.g. lines and figures.

The ONLYOFFICE suite can be used as a file converter. You can open a PDF file and convert it to another format. For example, you can turn your PDFs into editable DOCX files. Other compatible formats include ODT, TXT, DOTX, OTT, RTF, HTML, FB2 and EPUB.

Last but not least, ONLYOFFICE PDF Editor is compatible with PDF forms. This means that you can create new fillable forms and add interactive fields that can filled out with the required data. Text fields, drop-down lists, radio buttons, images, complex fields, combo boxes and other types come with flexible settings and user roles, which makes the process of creating PDF forms easier.

Read and edit PDF files on Windows, Linux and macOS with ONLYOFFICE Desktop Editors or work with them in your browser using ONLYOFFICE DocSpace, a powerful document collaboration platform with customized rooms and flexible access permissions:

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Pros:

• Suitable for all kinds of office documents, including PDFs
• Available on all popular platforms — web, desktop, mobile
• Powerful format conversion features
• Wide range of PDF editing tools, like drawings, annotations, text editing and objects
• Dark Mode
• Real-time collaboration for PDF files

Cons:

• Opening large PDF files sometimes takes long

2. Sumatra PDF

Sumatra PDF is a free and open source PDF viewer that is compatible with many document formats, including MOBI, EPUB, XPS, DjVu, CHM, and comic book formats — CBZ and CBR. The application is available only on Windows and runs on some older versions, like Windows Vista and Windows XP.

The main advantage of Sumatra PDF is the simplicity of its user interface. It’s equipped with the most essential features for a better reading experience and allows you to instantly access the recently opened files.

Sumatra PDF offers a portable version that can be used from an external USB drive, so you don’t even have to install the app.

The program supports a lot of hotkey commands to make working with PDFs even easier and is very good at opening large PDF files.

Pros:

• Simple user interface
• Portable version
• Fast performance
• Hotkey commands

Cons:

• No clients for Linux and macOS

3. Okular

Okular is a multi-platform open source PDF viewer that comes as part of the KDF software package. It’s designed for viewing PDF documents, comic books and e-books, browsing images and even opening Markdown documents.

Okular offers an advanced user interface, allowing you to add annotations and notes, select text and make it bigger with the Magnifier Mode, and leave bookmarks. The built-in Thumbnails panel makes navigation much easier, and the Content panel lets you access the required chapter with a few clicks.

Unlike other open source PDF readers, Okular offers the ability to view and verify digital signatures. Another advantage is that you can digitally sign PDFs yourself.

Being part of the of the KDE project, the app seamlessly works on a great number of Linux distros. There are also versions for Windows and macOS. When it comes to Windows, Okular is available only in the Microsoft Store.

Pros:

• Advanced user interface
• Support of e-signatures
• Available on all popular OS
• Compatible with a variety of formats

Cons:

• Comparatively high system requirements

4. Evince

Evince is a free and open source PDF reader that is compatible with multiple document formats. Apart from the Portable Document Format, it works with DjVu, PS, TIFF and XPS files and opens comic books — CB7, CBR, CBT and CBZ.

The app is a lightweight reader that covers the most essential functions, and its aim is to replace different document viewers that exist within the GNOME Desktop with one program.

Evince comes with a minimalistic interface and allows you to open, browse and print PDF files with ease. It makes navigation convenient due to the Drag&Drop feature and supports basic search functionality. Leaving annotations is also possible.

The viewer is available only on Linux and offers a lot of installation options so that Linux users can easily install it on their favourite distro.

Pros:

• Simple and intuitive user interface
• Various installation options
• Compatible with a variety of formats

Cons:

• No clients for Windows and macOS
• Opening large PDF files sometimes takes long

5. Xournal++

Xournal++ is not a usual PDF viewer. It’s an open source and cross-platform app for taking notes with PDF annotation support. That means that you can use this tool as a PDF reader with handwriting notetaking features.

The app is compatible with pressure-sensitive stylus and drawing tablets, so you can open your PDFs and create complex notes. You are allowed to keep track of your notes by using page previews.

Xournal++ has a built-in LaTeX editor, which allows you to create differential equations or electrical circuits on the pages of your PDF files. This feature is really useful if you need a PDF viewer for scientific and research purposes.

The app is highly customizable so you can create a unique toolbar layout. PDF export is another feature supported by the app.

Pros:

• Rich notetaking functionality
• Available on Windows, Linux and macOS
• Handwriting recognition
• Built-in LaTeX editor

Cons:

• User interface might look overloaded

6. zathura

zathura is a customizable and powerful document viewer with a minimalistic and space-saving interface. What makes this tool different from the other options on the list is that it focuses on keyboard interaction without using a mouse.

zathura uses a plugin-based system for supported document formats so you have the freedom to decide which file extensions you want to work with. This approach makes it possible to view not only PDF but also DjVu, PS and CB files.

You can easily customize zathura via a special configuration file. For example, you can change the predefined shortcuts and interface colours. Other interesting options include exporting images and attachments, opening encrypted documents and printing features.

Pros:

• Plugins for different formats
• High customization
• Mouse-free navigation
• SyncTeX support

Cons:

• Too minimalistic user interface

7. gImageReader

gImageReader is an open source PDF viewer with powerful OCR capabilities based on the well-known Tesseract engine. The program allows you to open PDF files and images, and is compatible with scanning devices, clipboard and screenshots.

gImageReader can generate PDFs by processing multiple images and files in one go. One of the biggest advantages of this reader is that you choose between manual or automatic recognition area definition while converting files.

The program works on Windows and various Linux distributions and offers multilingual support.

Pros:

• PDF generation from images and scanned photos
• OCR capabilities
• Ability to process the recognized text, including spell-checking
• Multilingual support

Cons:

• No macOS support

8. JPdfBookmarks

JPdfBookmarks is a simple but reliable PDF reader designed to allow you to create or edit bookmarks in your files. When working in this program, you can create bookmarks that link to a website or open a file on your computer when you click on them.

Using bookmarks in JPdfBookmarks, you can navigate quickly to a specific position in your PDF file. Moving bookmarks is simple as you can use your mouse with the drag’n’drop option.

JPdfBookmarks works on all popular platforms, including macOS, Linux and Windows and even lets you edit and add bookmarks from a command line.

Pros:

• Work with bookmarks
• Support for command-line operations
• Compatibility with Windows, macOS and Linux

Cons:

• No recent updates

9. Paperwork

Paperwork is not a traditional PDF reader. It does support PDF viewing but its main distinguishing feature is the ability to scan, import your personal documents to PDF and find them within seconds.

With this program, sorting all your scanned documents is a piece of cake as they are turned into searchable documents. Paperwork supports search across all your PDF files, too.

Paperwork stores all your files in a single directory, which can also be synchronized on many devices with services like Nextcloud, Syncthing and SparkleShare. In addition, the program has other interesting features, such as automatic page orientation detection and PDF page editing.

Pros:

• Intelligent sorting
• Compatibility with JPEG, hOCR and PDF
• Synchronization across various devices
• Editing features

Cons:

• No macOS support

10. Sioyek

Sioyek is an open source PDF reader that is great for technical books and research papers. This app makes it possible to search previously opened documents, table of contents and bookmarks. You can even generate a table of contents for your PDF file with a few clicks if there is none.

Portals are what make Sioyek outstanding. You can create portals from parts of different PDF files to other parts which are shown in a second window. That means that you don’t need to keep jumping between the two locations, which increases your productivity.

Sioyek can also highlight text with different colours, create bookmarks and preview references. There is another option which lets you extend the standard features using external commands and scripts.

Pros:

• Extensive navigation features
• External scripts and plugins
• Easy customization and configuration
• Searchable command palette

Cons:

• Keyboard-driven

11. Atril

Atril is the default viewing app of the MATE Desktop Environment for Linux that supports a lot of document formats, not only PDF. This multi-page document viewer has a simple user interface and allows you to open and print PS, EPS, DjVu, DVI, XPS and PDF files. It can also display CBR comics due to optional backend libraries.

When you open a document with Atril, you can search for the required text, copy the selected text to the clipboard, create hypertext and insert bookmarks for better navigation.

Pros:

• Simple and intuitive user interface
• Various supported formats, not only PDF
• Navigation tools
• Searchable command palette

Cons:

• No clients for Windows and macOS

12. Lector

Lector is a simple PDF reader for Windows users that is based on Electron and PDF.js. It comes with all basic features to navigate through PDF pages and adjust the desired zoom level for comfortable reading. Lector also has the Tabbed View feature allowing users to easily switch between multiple documents.

Lector’s left-side panel provides access to page thumbnails and document outlines. Such tools as page rotation, text selection and several scrolling modes (vertical, horizontal and wrapped) make it easier to use.

Pros:

• Intuitive interface
• Several scrolling modes
• Tabbed View
• Navigation tools

Cons:

• No recent updates

How to choose the best open source PDF reader

Taking into consideration the fact that there are a lot of PDF viewing tools that perform the same operations but in different ways, sometimes it might be difficult to choose the ideal application. Your choice depends on your preferences. Opt for:

• ONLYOFFICE PDF Editor if you need a comprehensive office suite for your OS with PDF viewing and editing functionality
• Sumatra PDF if you run Windows and need a simple PDF reader with intuitive interface elements
• Okular if you happen to digitally sign PDFs
• Evince if you are a Linux enthusiast
• Xournal++ if you have to annotate PDF files very often
• zathura if you need a simple PDF viewer with mouse-free navigation
• gImageReader if you need OCR features for your PDF files
• JPdfBookmarks if you often work with bookmarks
• Paperwork if you need a PDF viewing tool for scanned PDF files and images
• Sioyek if you need to open and read technical books and research papers
• Atril if you need a universal document viewer for Linux
• Lector if you need a simple and lightweight PDF viewer for Windows