Compare software

Adobe Acrobat ReaderOkular
Freemium

Free to use; editing and conversion require a paid Adobe Acrobat subscription.

 Free

Free and open source under the GPL.

Windows, macOS, Android, iOS Windows, macOS, Linux
  • Faithful rendering of complex PDFs and forms
  • Form filling, signing and annotation included free
  • One viewer for a very wide range of document and comic formats
  • Annotations are stored separately, so the original file is untouched
  • Frequent prompts to upgrade to paid Acrobat
  • Large install compared with lightweight readers
  • Pulls in KDE libraries on non-KDE desktops
  • It is a viewer and annotator, not a PDF editor
Downloadable app Downloadable app
Closed source Open source
License: Proprietary License: GPL-2.0
Not stated if an account is needed Not stated if an account is needed
Works offline Not stated if it works offline

Checked October 1, 2026

Checked September 22, 2026

Catalog facts only. Anything “not stated” is unconfirmed. Check full listings for details.