Download

Get Portwhistle.

A network monitor and firewall for your Mac. Everything it sees stays on your machine.

Download for macOS

Requires macOS 13.0 or later.

Install

Installing it

  1. Drag Portwhistle to your Applications folder.

    Open the file you downloaded, then drag the app across.

  2. Open it, and approve it when macOS asks.

    macOS asks you to allow Portwhistle to filter network traffic, and opens System Settings for you. You need to be an administrator of the Mac.

  3. That is it.

    Portwhistle starts watching straight away. It blocks nothing until you tell it to.

Uninstall

Removing it

Turn filtering off before you delete the app. Only the app can switch off its own filter, so deleting it first leaves the filter behind.

  1. Open Portwhistle and turn filtering off.

    Click the status pill at the top right of the window.

  2. Quit Portwhistle.

  3. Drag it from Applications to the Trash.

    Your rules and history stay on your Mac in case you reinstall. The Privacy Policy says where they live and how to remove them.