What Apple’s Firewall Really Does
The built-in macOS Firewall (System Preferences → Network → Firewall) only filters incoming connections. It was designed to protect your Mac from network attacks — port scans, unauthorised remote access, and similar threats. That’s useful but incomplete. It does nothing to control what your Apps SEND out. Any app on your Mac can freely connect to any server, send telemetry, contact trackers, and transfer data — the macOS Firewall will neither stop it, warn you, nor log it.
The Missing Half of Network Security
Think of it this way: Apple’s Firewall is a security guard checking who enters the building. But no one checks what leaves the building. NetMute adds outgoing connection control — it monitors each app’s network activity, identifies tracker connections, assigns Privacy Scores, and gives you the power to block any app’s internet access. You should keep the macOS Firewall enabled (for incoming protection) AND use NetMute for outgoing control.
Built-in Free vs. Premium Add-on
Apple’s Firewall is free and built into every Mac. NetMute is a one-time purchase on the Mac App Store. The macOS Firewall has zero configuration for outgoing traffic — there’s nothing to adjust. NetMute offers a full dashboard with per-app rules, traffic monitoring, Privacy Scores, and network profiles. They are not competitors — they complement each other.
Do You Need Both?
Yes. Keep the macOS Firewall enabled for incoming protection. Add NetMute for outgoing control, tracker detection, and Privacy intelligence. The macOS Firewall protects you from external attacks. NetMute protects you from your own apps leaking data. Both threats are real and both need protection. Using only the macOS Firewall is like locking the front door but leaving all the windows open.