Radio Silence is a lightweight Mac firewall that does one thing extremely well: it stops apps from connecting to the internet without your permission. Unlike macOS's built-in firewall, which only handles incoming connections, Radio Silence focuses on outbound traffic — the kind that lets apps quietly phone home with your data. It runs invisibly in the background, requires no menu bar icon, and has no effect on your Mac's performance. A one-time purchase of $9 unlocks it permanently, with no subscription required.

Key Features

• Outbound Connection Blocking: Stop any app from accessing the internet with a single click — including helper apps, background processes, daemons, and XPC services that most users never see.
• Real-Time Network Monitor: Watch every active network connection on your Mac as it happens. If an app is misbehaving, you can identify it and block it immediately.
• Completely Invisible Operation: No menu bar icon, no open windows required. The firewall activates automatically at startup and stays active even after you close the app.
• No Pop-Up Alerts: Radio Silence does not interrupt your work with connection alerts. You build your block list manually, and the firewall enforces it silently.
• One License, All Your Macs: A single purchase covers all the Macs you personally own — not tied to one machine.
• Works with macOS Tahoe: Fully compatible with macOS Tahoe (26), Sequoia (15), Sonoma (14), Ventura (13), and back to Catalina (10.15) on both Apple Silicon and Intel Macs.

Quiet Blocking vs. Alert-Based Firewalls

Radio Silence takes a different approach from tools like LuLu. Rather than asking you to approve or deny each outbound connection as it happens, Radio Silence lets you build a simple block list at your own pace. Apps on the list are silently blocked. Apps not on the list connect freely. There are no interruptions, no decisions to make mid-workflow, and no learning curve. This makes it a better fit for users who already know which apps they want to silence — for example, blocking Adobe Creative Cloud from phoning home, or stopping a utility app from checking in with its developer servers. If you want real-time alerts for every new connection, LuLu is the better tool. If you want quiet, permanent blocking with zero friction, Radio Silence is the one to reach for.

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Frequently Asked Questions (FAQ)

How is Radio Silence different from the built-in Mac firewall?

The built-in macOS firewall only blocks incoming connections — it does nothing to stop apps from sending data out. Radio Silence is the opposite: it focuses entirely on outbound connections, which is where most privacy concerns actually live. The two tools complement each other and can run at the same time.

Does Radio Silence show alerts when an app tries to connect?

No. Radio Silence does not use pop-up alerts. Instead, you use the network monitor to see what is connecting, then manually add apps to your block list. Once an app is blocked, it stays blocked silently. This makes Radio Silence much less disruptive than alert-based firewalls, but it does mean you need to be proactive about checking the monitor.

Does the firewall stay active if I close the app?

Yes. The Radio Silence firewall runs as a background service and activates automatically every time your Mac starts. You only need to open the app when you want to make changes to your block list. Closing the window or quitting the app does not disable the firewall.

Can Radio Silence block Adobe Photoshop or other creative apps from phoning home?

Yes. Radio Silence works with any app installed on your Mac, including Adobe Creative Cloud apps, Microsoft Office, and any other software that makes outbound connections. You simply add the app — or its helper processes — to your block list.

Is there a free trial?

Yes. The downloadable installer includes a free 24-hour trial with no feature limitations. After purchase, there is also a 30-day money-back guarantee with no questions asked.

Does Radio Silence work on Apple Silicon Macs?

Yes. Radio Silence 3 runs natively on Apple Silicon (M1, M2, M3, M4) and Intel Macs. It supports macOS Tahoe, Sequoia, Sonoma, Ventura, Monterey, Big Sur, and Catalina.