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Home/Categories/Business & Productivity/Okular
icon of Okular

Okular

Open source alternative to Adobe Acrobat, Foxit PDF Editor and Nitro PDF

  • 1.5K stars
  • Active this week
  • Last commit 2 days ago

Last verified Oct 20, 2026

Render PDFs, EPUBs, comics, and Markdown files with a cross-platform open source document viewer from KDE.

Visit websiteGitHub1.5K stars
image of Okular
TL;DR

Okular is KDE's universal document viewer for PDFs, PostScript, comic books, images, and other document formats with annotation support. It replaces proprietary PDF readers for users who want a local viewer that handles more than PDFs. Best for Linux and cross-platform users who annotate and read many document types.

Read the full breakdownHide the full breakdownWho it is for, how it works, trade-offs and the FAQ
who it's for

Who Okular is for#

Researchers annotating documents locally

Use Okular to read and mark up PDFs and related document formats without relying on a proprietary cloud viewer.

Skip if:

Your workflow requires collaborative web review and shared comments.

Linux users needing one document viewer

Use Okular as a broad document viewer for PDFs, PostScript, comics, images, and annotated files.

Skip if:

You need a specialized editor for rewriting PDF text or performing OCR.

the problem

The problem it solves#

Many document viewers are either narrow PDF readers or commercial editors with features most readers do not need. Users working across PDFs, books, comics, and image-based documents can end up juggling multiple apps.

Annotations add another layer of friction. Students, researchers, and knowledge workers need highlights, notes, forms, and signatures without turning every document into a cloud workflow.

how Okular solves it

How it solves it#

Multi-format document viewing

Views and annotates formats including PDF, PostScript, comic book formats, and image formats, so one app can cover several reading workflows.

PDF annotations

Supports native PDF annotations, giving users local tools for highlights, notes, and review workflows.

KDE desktop integration

Comes from the KDE ecosystem, making it a natural document viewer for Linux desktop users while also offering broader platform availability.

strengths · trade-offs

Strengths and trade-offs#

Strengths

  • More than a PDF readerOkular covers several document and image formats, so users do not need a separate app for every reading format.
  • Strong local annotation workflowNative PDF annotation support makes Okular useful for study, review, and document markup without uploading files to a cloud service.

Trade-offs

  • -Not a full PDF editorOkular is primarily a viewer and annotation tool. Users who need deep PDF editing, OCR, redaction, or layout changes should use a dedicated editor.
tech stack · detected from GitHub

What it's built on#

Languages
CC++
frequently asked

FAQ#

What is Okular used for?

Okular is used to view and annotate documents such as PDFs, PostScript files, comic books, and image-based documents.

Can Okular annotate PDFs?

Yes. Okular supports native PDF annotations for local document review workflows.

Is Okular a PDF editor?

Okular is primarily a document viewer and annotation tool. It is not a full PDF editor for OCR, redaction, or layout rewriting.

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