Compare software

simplewallOpenSnitch
Free

Free and open source under the GPL 3.0.

 Free

Free and open source under the GPL.

Windows Linux
  • A plain allow and block list rather than a stream of pop-ups
  • Internal block list aimed at Windows telemetry
  • Prompts on every new outbound connection, so unexpected traffic becomes visible
  • Blocks ad, tracker and malware domains system-wide
  • The project itself says it is for advanced users
  • Not a Windows Firewall interface; it uses a separate rule system
  • Linux only
  • The first days are a stream of prompts until your rules settle
Downloadable app Downloadable app
Open source Open source
License: GPL-3.0 License: GPL-3.0
No account needed No account needed
Works offline Works offline

Checked September 21, 2026

Checked September 21, 2026

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