Privacy Policy

Performance Monitor for macOS · last updated 30 July 2026

Performance Monitor collects nothing about you. There is no telemetry, no analytics, no crash reporting service, no account, and no server of ours for anything to be sent to. This page explains what that means in practice, and describes the handful of network requests the app does make so that nothing is left implicit.

The short version: everything the app measures stays on your Mac. It talks to the network only to check for updates, and (if you leave those features on) to look up your public IP address and to measure network latency. It never sends anything about your usage, your machine, or your metrics anywhere.

What the app collects about you

Nothing. No usage statistics, no device identifiers, no diagnostics, no analytics of any kind. The app has no code that reports on how you use it, and being open source, that is something you can verify rather than take on trust: the complete source is public under the MIT licence.

What stays on your Mac

All measurements the app takes (CPU, memory, network throughput, disk activity, GPU, temperatures, fan speeds, SSD wear, battery health, Bluetooth device names and battery levels, per-process usage) are read from macOS on your machine and displayed on your machine. They are never transmitted.

Some of it is written to disk locally, in ~/Library/Application Support/PerformanceApp/:

History: if you enable it, sampled metrics are stored so the History window can show trends over time.
Network data usage totals: daily download and upload totals, if that feature is on.
Crash reports: captured through Apple's MetricKit and written as local JSON files. These are not uploaded anywhere, not to us and not to Apple on our behalf. If you want to share one, you have to send it yourself.
Preferences: your settings, in the standard macOS preferences location.

You can delete any of it at any time. Removing that folder resets the app's stored data.

Network requests the app makes

There are three, and only three:

Update checks: the app asks api.github.com whether a newer release exists, and downloads it from GitHub if you choose to install it. GitHub sees the request the way any website sees a visitor: your IP address and the request itself. Nothing identifying you or your machine is added by us. Downloads are verified against an Ed25519 signature before they are unpacked.
Public IP lookup: the Network view can show your public IP address. Finding it out requires asking something outside your network, so the app asks api.ipify.org, a service that returns your IP address and nothing else. This is a setting you can switch off, and when it is off no request is made.
Latency measurement: the latency figure in the Network view is measured by sending a small request to a host you pick in Settings: Apple, Cloudflare, Google or Quad9. That host sees a request from your IP address, as it would from any device. You choose which one, and the app contacts no other.

Beyond those, the app opens links in your browser when you click them, such as the GitHub repository or the sponsorship pages. Those are ordinary visits to those sites, subject to their own policies, and only happen when you click.

Permissions the app asks for

Bluetooth: to list your paired devices and read their battery levels, including AirPods. Declining it means those readings are unavailable; everything else works normally.
Notifications: to deliver threshold alerts, if you enable them. Also optional.

Neither permission is used for anything beyond what it says, and neither sends data anywhere.

This website

This site is static and hosted on GitHub Pages. It sets no cookies, runs no analytics, and loads nothing from third parties. GitHub, as the host, processes ordinary server request data such as IP addresses in order to serve the page; that is covered by GitHub's privacy statement.

Children

The app is not directed at children and collects no personal data from anyone, of any age.

Changes

If this policy changes, the date at the top changes with it, and the edit is visible in the page's history like everything else in the repository.

Contact

Questions about privacy, or something in this policy that does not match what the app does, are best raised as an issue on GitHub. For anything you would rather not discuss in public, use the Report a vulnerability form on the Security tab, which opens a private thread.