Kestrel Free costs nothing and needs no account. You unlock Pro later with a key in the same app.
macOS 13+
File: kestrel-mac.dmg
Kestrel shows every connection of the programs on your Mac and blocks data collectors for all programs through a small DNS filter.
Prompts and rules per program come with the signed version and its system extension.
Windows 11
File: kestrel-windows.exe
A service filters every connection per program through the Windows Filtering Platform, even while the window is closed. The installer sets it up and removes it again.
Linux (.deb)
File: kestrel-linux.deb
A service checks every new connection through nftables. The package sets it up, and instead of a signature Kestrel shows the package a program comes from.
On the first start Kestrel guides you through the setup. Each page checks by itself whether its step is done.
Open kestrel-mac.dmg, drag Kestrel into the Applications folder and start the app from there.
From the first start Kestrel shows every connection with program, destination, country and data volume. There is nothing to set up for this.
“Set up DNS filter” installs the filter on your Mac; macOS asks for your password once. If the filter ever stops answering, a watchdog restores the previous DNS settings at once.
You can also continue without the DNS filter and set it up later in the settings under Data collectors.
Questions about the setup
Kestrel