Zen

About

Zen is a free, open-source (MIT) app for Windows, macOS, and Linux that blocks ads and trackers system-wide, not just in your browser. It runs a local proxy on your computer and sets it as the system proxy, so browsers and most apps send their traffic through it. Requests to ad, tracking, and malware servers are blocked, and on web pages Zen also hides empty ad slots. Zen ships with filter lists for ads, trackers, and malware enabled, includes 35 regional lists, and lets you add your own lists or write custom rules.

Zen makes its filtering decisions on your Mac and states that it does not collect your browsing data or send it anywhere. To filter encrypted (HTTPS) connections, Zen asks you to install a local root certificate on first run. The website says the certificate and its private key are generated on your device and never leave it, and you can remove the certificate from Zen's settings at any time. The macOS download is available for Apple silicon and Intel Macs, or through Homebrew.

Zen works with browsers such as Chrome, Firefox, Safari, Edge, Opera, and Brave, as well as desktop apps that use the system proxy settings. Apps with their own networking stack or certificate pinning bypass Zen or may need additional setup.