KillerPDF vs Sioyek
Comparing two open source alternatives to Adobe Acrobat and Foxit Reader and Nitro PDF . Use the comparison below to decide which one fits your needs.
KillerPDF
GPL-3.0Lightweight, fully portable PDF editor for Windows. Edit, merge, annotate, and sign PDFs locally with no subscription, accounts, or hidden telemetry anywhere.
Sioyek
GPL-3.0Cross-platform PDF viewer focused on textbooks and research papers with smart navigation, marks, bookmarks, and bibliography jumping.
Side-by-side comparison
| KillerPDF | Sioyek | |
|---|---|---|
| License | GPL-3.0 | GPL-3.0 |
| Self-hostable | No | No |
| GitHub Stars | 3,363 | 9,773 |
| Forks | 253 | 357 |
| Open Issues | 29 | 321 |
| Last Commit | Aug 5, 2026 | Aug 15, 2026 |
| First Released | Apr 16, 2026 | Jul 11, 2021 |
| Categories | ||
| Tags |
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