Documents and notes
Nitro PDF Pro alternatives
2 open-source projects that already do this job. Free to use - not free to run, which is what the numbers on the right are for.
The projects
Stirling-Tools/Stirling-PDF★89,037 GitHub starslicence unclearCross-platform PDF editor that lets users view, annotate, edit, and save PDFs in a desktop/web app.Open on GitHub ↗SteveTheKiller/KillerPDF★3,289 GitHub starsGPL-3.0 licenceWindows PDF application for viewing, annotating, OCRing, editing text, signing, and managing PDFs.Open on GitHub ↗
What you give up either way
- Nitro’s built-in AI redaction and advanced AI tools
- Enterprise-grade eSign compliance (eIDAS/AES/QES) and ID verification options
- Nitro Analytics and built-in admin/usage dashboards
- Cross-platform production polish and commercial installers
- Prebuilt integrations (Salesforce, SharePoint, PowerAutomate) and enterprise support
An open-source project doing the core job proves a replacement is possible. It does not prove it matches Nitro PDF Pro, and it does not prove anyone has run it for a month. How we decide.