Outline vs SumatraPDF
Comparing two open source alternatives. Use the comparison below to decide which one fits your needs.
Outline
BSL-1.1The fastest growing-team knowledge base — beautiful, realtime collaborative, feature packed, and markdown compatible Notion and Confluence alternative.
SumatraPDF
GPL-3.0Lightweight, free PDF, eBook, and comic reader for Windows that launches instantly and stays out of the way; multi-format support with minimal interface.
Side-by-side comparison
| Outline | SumatraPDF | |
|---|---|---|
| License | BSL-1.1 | GPL-3.0 |
| Self-hostable | Yes | No |
| GitHub Stars | 40,870 | 17,739 |
| Forks | 3,611 | 2,055 |
| Open Issues | 78 | 47 |
| Last Commit | Oct 12, 2026 | Oct 12, 2026 |
| First Released | May 22, 2016 | Oct 2, 2012 |
| Categories | ||
| Tags |
GitHub stars over time
GitHub stars over time
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