What leaves your Mac

Every connection, and why

What	Where	What is sent
Malware fingerprints When you run a malware scan or update definitions.	bazaar.abuse.ch	Nothing about you. MacTidy downloads a public list of known malware fingerprints, around 40 MB, and compares your files against it on your own machine. Your files are not uploaded to be scanned.
Licence check On activation, and periodically while subscribed.	api.lemonsqueezy.com	Your licence key and a device name, so the subscription can be tied to a machine. No file names, no scan results, no contents.
Homebrew installer Only if you ask MacTidy to install Homebrew.	raw.githubusercontent.com	Nothing. It fetches Homebrew's official install script, the same one Homebrew's own site tells you to run, and opens it in Terminal so you can see it work.
The AI features Only if you run a local model.	localhost:1234 localhost:11434	These are LM Studio and Ollama on your own Mac. The traffic does not leave the machine. If you do not run either, the features stay off. There is no cloud model behind them.

Links that open in your browser

These are not connections MacTidy makes. They are links it can hand to your browser when you click something, and your browser behaves normally.

• VirusTotal. On a flagged file you can press "Look up on VirusTotal". That opens a page whose address contains the file's fingerprint. The fingerprint is a hash, not the file, but it does reach VirusTotal, and only because you clicked.
• Checkout and subscription management, which open our payment provider's pages.
• Apple support pages and settings panes, when a step points you at one.

What there is none of

• No analytics or product telemetry. There is no third party SDK in the app for it.
• No crash reporting service.
• No account. You do not create one, and there is nothing to log in to.
• No advertising identifiers, no fingerprinting, no tracking pixels in the app.
• No uploading of files, file names, paths or scan results.

Being precise about one thing

Some tools say "everything is 100% local" and then quietly open a socket. We would rather be exact. MacTidy does use the network, for the four things in the table. What it does not do is send your data anywhere. "Your files never leave this Mac" is the promise, and it is a different claim from "this app never connects to anything".

Checking for yourself

You do not have to take our word for it. Point Little Snitch, LuLu or any outbound firewall at MacTidy and watch. If you see a connection that is not on the list above, tell us and we will either explain it or remove it.

The Safest security level inside MacTidy will in fact prompt you to install an outbound firewall, which will then monitor MacTidy too. That is the correct outcome.