Stirling-PDF — The #1 Open-Source PDF Application on GitHub. Here are the closest alternatives and when to pick each.
AI verdict· generated Jun 24, 2026How we pick
Stirling-PDF is great for businesses that require secure, robust PDF processing. However, if you're considering alternatives based on specific use cases, here's a breakdown of which tool might be best for your needs:
If you want a personal knowledge manager: Go with Obsidian. This is ideal for personal organization and project management, providing an intuitive way to manage notes and workflows without the PDF focus of Stirling-PDF.
If you need an AI-powered document interaction: Choose private-gpt. This tool allows you to interact with documents using AI, making it suitable for developers and privacy-conscious users. While it lacks the direct PDF editing capabilities of Stirling-PDF, its privacy-first approach is essential for confidential documents.
If you’re a designer or part of a creative team: Penpot is your best bet. This open-source tool is tailored for design and prototyping, enabling teams to collaborate without vendor lock-in, a feature absent in Stirling-PDF.
If you’re looking for project and issue management: Consider Linear. While not a PDF tool, it's fantastic for software teams looking for fast issue tracking and project management solutions, especially if your documentation is tied to product development.
Choose based on what specific features or use cases are most critical for you or your team.