Live sensor temperatures
See current and peak values for CPU, GPU, memory, SSD, battery and ambient sensors. Only sensors that return a plausible reading on your Mac are listed.
Open source · macOS 14+ · Universal binary · System Monitoring
Know before your Mac
slows down.
ThermalThrottleWatch lives in your menu bar and shows the system thermal state and sensor temperatures at a glance. Click the thermometer for details, and get a notification when throttling begins.
Free & MIT licensed · Apple Silicon & Intel · Latest release
Features
One question, answered clearly.
Is your Mac under thermal stress right now? Everything here exists to answer that, read-only and on-device.
Thermal state in the menu bar
A thermometer icon is tinted by the system state: Nominal, Fair, Serious or Critical. Optionally show the hottest sensor's temperature beside it.
Alerts for throttling and recovery
Get notified when the state reaches Serious or the hottest sensor passes your threshold (60 to 105 °C). A second notification tells you when it has cooled down.
30-minute trend and event log
A sparkline tracks the hottest sensor, and each throttle episode is logged with its start time and duration for 14 days.
Calm, tunable alerts
Readings are smoothed, recovery needs a 3 °C drop, and the same condition notifies at most once every 5 minutes. Choose Celsius or Fahrenheit and a 2, 5 or 10 second refresh.
Read-only and private
No fan control, no accounts, no servers and no analytics. If sensors cannot be read, it falls back to the system thermal state and tells you so.
Screenshots
See it in action.
Install
Up and running in a minute.
ThermalThrottleWatch is open source and not notarized with a paid Apple Developer ID, so macOS needs one extra step the first time.
- Download ThermalThrottleWatch-macOS.zip and unzip it.
- Move ThermalThrottleWatch.app to your Applications folder.
- Clear the quarantine flag once, then right-click the app and choose Open:
xattr -cr /Applications/ThermalThrottleWatch.app
- Allow notifications when prompted (or in System Settings → Notifications) so alerts can reach you no other permissions are needed.
Download
Get ThermalThrottleWatch for macOS
Free, forever. Built for macOS 14 Sonoma or newer, Apple Silicon and Intel.
Not notarized: on first launch right-click ThermalThrottleWatch.app → Open.
- macOS 14 Sonoma+
- Universal (Apple Silicon + Intel)
- MIT licensed · open source
- No ads, no accounts, no telemetry
- Built with Claude Code · how and why
FAQ
Questions, answered.
Is ThermalThrottleWatch really free and open source?
Yes. It is released under the MIT license, with no ads, accounts or paywalls. The full source is on GitHub, and you can support development with the optional Support button.
What permissions does it need?
Only notifications, so it can warn you about throttling and recovery. Launch at login is optional, and it never asks for Accessibility, Screen Recording, Microphone, Camera or Location.
Where is my data stored?
On your Mac only. Settings are saved in app preferences, and the 14-day throttle event log is a JSON file in Application Support. Nothing is sent anywhere.
Why isn't the app notarized?
Notarization requires a paid Apple Developer account, which this free project doesn't have. Right-click the app and choose Open once to approve it, or build it from source with Xcode.
Was this written by AI?
Yes. ThermalThrottleWatch was generated by Claude Code from a written spec as a clean-room reimplementation, with no code or assets from any commercial app. The full source is on GitHub under MIT, so you can read every line before you run it. It has had less human review than a hand-written app, so bug reports are welcome.
Support ❤️
Built by one person, given away for free.
ThermalThrottleWatch is a free, open-source alternative to paid utilities. If it earns a spot on your Mac, a coffee keeps the updates coming.
☕ Support Or on Ko-fi