Compare software

OpenSnitch vs Portmaster: catalog facts
OpenSnitch	Portmaster
Free Free and open source under the GPL.	Freemium Free and open source under the GPL 3.0. Network history search, per-app bandwidth and the…
Linux	Windows, Linux
Prompts on every new outbound connection, so unexpected traffic becomes visible Blocks ad, tracker and malware domains system-wide	Blocks known trackers and malware with no configuration Live list of every connection, attributed to the program that made it
Linux only The first days are a stream of prompts until your rules settle	Windows and Linux only Network history search and bandwidth figures are paid features
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
Official website Full listing and sources Checked September 21, 2026	Official website Full listing and sources Checked September 21, 2026

Catalog facts only. Anything “not stated” is unconfirmed. Check full listings for details.