Okular icon
Okular icon

Okular

 456 likes

Multi-platform document viewer offering extensive format support, including PDF, comics, images, EPUB, and Markdown, with annotation tools, sidebar previews, text-to-speech, DRM management, cross-platform compatibility, and integration with KDE Frameworks libraries.

Okular screenshot 1

License model

  • FreeOpen Source

Application types

Country of Origin

  • DE flagGermany
  • European Union flagEU

Platforms

  • Windows
  • Linux
  • BSD
  • KDE Plasma
  • Snapcraft
  • Linux Mobile
  • Flathub
  • Haiku
4.2 / 5 Avg rating (50)
456likes
43comments

Features

Suggest and vote on features

Properties

  1.  Lightweight
  2.  Privacy focused

Features

  1.  PDF annotation
  2.  Text Highlighting
  3.  Tabbed interface
  4.  Dark Mode
  5.  Ad-free
  6.  Low memory usage
  7.  KDE
  8.  Works Offline
  9.  Customizable shortcuts
  10.  Text to Speech
  11.  Fill PDF Forms
  12.  No Tracking
  13.  Export to PDF
  14.  No registration required
  15.  Sign PDF files
  16. Microsoft 365 Copilot icon  Compatible with Microsoft Office
  17.  Trim margins
  18.  Ebook Conversion
  19.  Full-Text Search
  20.  Multiple languages

 Tags

Okular News & Activities

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Recent activities

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Okular information

  • Developed by

    DE flagKDE
  • Licensing

    Open Source and Free product.
  • Rating

    Average rating of 4.2 (50 ratings)
  • Alternatives

    113 alternatives listed
  • Supported Languages

    • English
    • Spanish
    • Ukrainian
    • Russian

Our users have written 43 comments and reviews about Okular, and it has gotten 456 likes

Okular was added to AlternativeTo by gyorgyjano on Apr 24, 2009 and this page was last updated May 13, 2025.

Comments and Reviews

   
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Comment summary: Okular receives praise for being open source and cross-platform with rich annotation features. It's seen as a good alternative for lightweight PDF reading, but lacks intuitive form filling and text editing. Some users note interface shortcomings and a higher than expected resource usage. Overall, it has potential but requires improvements, especially in usability and performance, to compete with more robust options like Adobe Reader.
Top Positive Comment
Rodrigo1
Sep 24, 2019
18

It is a very good alternative to Sumatra, and evidently its greatest advantage over this are the PDF annotations. Some functions that I use a lot in Sumatra and that are NOT in Okular are:

  • Open multiple files in tabs, in a single window. Okular works Office style, it will open one window per file, which is not practical.

  • File history, and possibility to reopen them ALL automatically when starting the program.

  • In the Windows version, Okular occupies more than 400 Mb, while Sumatra less than 20 Mb.

Finally, a very commented problem is the lack of a "standard" installer in Windows. I had the same problem, and after abandoning all this and trying MuPDF (quite limited) I gave it a last chance, and it turns out that IF THERE IS an installer that is very hidden...the link is below.

There you will find the typical *exe, and also a 7z compressed that will make the portable version (the executable is in the bin folder). If you navigate within that web, you will also find the "Nightly" versions of Okular, and also other applications of the KDE community


Mensaje Original:

Es una muy buena alternativa a Sumatra, y evidentemente su mayor ventaja respecto a esta son las anotaciones en PDF. Algunas funciones que uso bastante en Sumatra y que NO están en Okular son:

  • Abrir múltiples archivos en pestañas, en una sola ventana. Okular trabaja al estilo Office, se abrirá una ventana por archivo, lo cual no es práctico.

  • Historial de archivos, y posibilidad de reabrirlos TODOS automaticamente al iniciar el programa.

  • En la version de Windows, Okular ocupa mas de 400 Mb, en cambio Sumatra menos de 20 Mb.

Finalmente, un problema bastante comentado es la falta de un instalador "estándar" en Windows. Tuve el mismo problema, y tras abandonar todo esto y probar MuPDF (bastante limitado) le di una última oportunidad, y resulta que SI EXISTE un instalador que esta muy oculto...lo encuentran en:

https://binary-factory.kde.org/view/Windows%2064-bit/job/Okular_Release_win64/

Alli encontraran el típico *exe, y tambien un comprimido 7z que hará las veces de versión portable (el ejecutable esta en la carpeta bin). Si navegan dentro esa web, también encontrarán las versiones "Nightly" de Okular, y tambien otras aplicaciones de la comunidad KDE.

Brouware
Sep 29, 2022

Although this might have been true in the past, today Okular does support tabs. You can enable it in the settings.

Farrukh
May 31, 2024

Thanks @Brouware. You are a life saver. :)

Top Negative Comment
CanadianCricket
Nov 11, 2024
1

Okular on Windows does not support epub. Source: [https://forums.linuxmint.com/viewtopic.php?t=195708](https://forums.linuxmint.com/viewtopic.php?t=195708)

I don't know its .pdf capabilities.

jadethaum
Jan 11, 2025
1

There's a lot to like here, because it is a competently assembled and FOSS reader that does PDF and markdown. But on PDFs, the use of forms - which is my main reason to interact with PDFs - feels hopelessly clunky for now, superimposing giant text boxes over the PDF instead of transparent guide boxes. If you don't edit PDFs as much as I do you may still like it, and I'd certainly fall back to it in a pinch, but it's just a little too intrusive on that one thing for me.

TBayAreaPat
Jan 1, 2025
0

Open Source and Free, it looks like a good choice for editing PDFs. If you look far right on the pull down menu under highlite, you will see a text option. Does not open .rtf files. Another perhaps much more lightweight and free option with similar abilities is Ashampoo PDF Free icon Ashampoo PDF Free

dwiki24
Nov 12, 2024
-1

Lightweight and have a text highlighting feature.

Hope in the future have a merge and organize pages.

Pholith
Sep 21, 2024
2

Good software but still can't edit text.

Shaz Shah
May 31, 2024
2

My use case for an alternative to Acrobat Reader is due to it having a large footprint resource-wise on my computer when I just need to read PDF docs and fill the occasional form. Plus, I don't think I will ever need the paywalled functionality that is sitting there waiting to be used once you have a subscription.

So, I've been on the fence for a while between SumatraPDF and Okular. They are both very lightweight and capable. However, I finally settled with Okular due to the forms (which I do use) and annotation support.

However, I do have a wish list of some improvements:

  • Have support with fast scrolling with the mouse wheel. I have the MX Master 2S, so when I do the fast scroll, the page scrolls up/down slowly.
  • The settings/configuration interface can do with a face lift.
  • Enable tab support. I did find the option (eventually) in the settings, but the PDFs still open in separate windows. Maybe I'm doing something wrong.

There is one "downside" to Okular if you are counting the MBs used up by apps. While lightweight, it does take considerably more resources than SumatraPDF.

EDIT: I have since found a nuance to the tab behaviour. If you already have Okular open with a document, and you try to open another one via the File Open or File Open Recent menus, it does get loaded into a new tab. Drag-n-drop also works. The problem seems to be with opening another doc from File Explorer.

EDIT 2: Found that it is a known issue 427953 – Unique instance and open in tabs ignored

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What is Okular?

Okular is a multiplatform document viewer developed by the KDE community and based on Qt and KDE Frameworks libraries. Features:

  • Supported Formats: PDF, PS, Tiff, CHM, DjVu, Images, DVI, XPS, ODT, Fiction Book, Comic Book, Plucker, EPub, Fax
  • Sidebar with contents, thumbnails, reviews and bookmarks
  • Annotations support
  • Reading text aloud using the Qt Speech module
  • Supports DRM restrictions of PDF files but this can be turned off in the options under "Obey DRM limitations"

Okular Videos

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