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Adobe Acrobat ReaderSumatra PDF
Freemium

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

 Free

Completely free and open source with no ads, bundled software or subscription. No account…

Windows, macOS, Android, iOS Windows, Command line
  • Faithful rendering of complex PDFs and forms
  • Form filling, signing and annotation included free
  • Opens PDF, EPUB, MOBI, FictionBook, CBZ/CBR/CBT/CB7, DjVu, XPS, CHM, SVG and many image formats including HEIC and AVIF
  • Lightweight and fast; the portable single .exe build writes nothing to the registry
  • Frequent prompts to upgrade to paid Acrobat
  • Large install compared with lightweight readers
  • Windows only (Windows 7 through 11; XP and Vista need version 3.1.2); no macOS or Linux version
  • Only unencrypted EPUB and MOBI/AZW ebooks open; DRM-protected files are not supported
Downloadable app Downloadable app
Closed source Open source
License: Proprietary License: GPL-3.0
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 20, 2026

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