SumatraPDF
FreeSumatraPDF is a small, fast, free reader for PDF, EPUB, MOBI, comic books and other documents on Windows.
About SumatraPDF
SumatraPDF is a lightweight document reader for Windows. It opens PDF, EPUB, MOBI, CBZ, CBR, FB2, CHM, XPS and DjVu files, and it is known for starting almost instantly and using little memory.
The interface is minimal, with keyboard shortcuts for navigation and a portable version that runs without installation. It focuses on reading rather than editing, so it does not include form filling or heavy annotation tools. It is maintained by a small team, with source code and releases on GitHub. Installer and portable builds are available, and the app uses tabs to keep several documents open at once.
It suits people who want a quick, no-fuss viewer for PDFs and e-books, including on older or low-spec machines. It is free and open source under the GPL-3.0, with no ads or account. For editing, signing or advanced annotation, you will need a different tool. It is a Windows-only application.
Choose the portable build if you want no installation. It is a viewer, so pair it with another tool for editing PDFs.
Version history
1 release tracked- Bug fixes and performance improvements
Frequently asked
Is SumatraPDF free?
Yes. It is free and open source under GPL-3.0.
Does it need an account?
No. There is no sign-up or telemetry account.
Which platforms does it run on?
Windows only.
Where does the download link go?
Directly to sumatrapdfreader.org or the official app store for your platform. PlanetSofts never rehosts installers or adds wrappers, and these links were last verified Oct 6, 2026.