How hot is too hot?
Apple designs Mac laptops to be used in rooms between 10° and 35° C (50° to 95° F). Inside that range, the Mac manages its own temperature: fans speed up, and if that's not enough, macOS lowers performance until the chip cools down. You won't damage it by working hard, but a Mac that's constantly hot will feel slower.
To see whether macOS has had to slow down for heat, open Terminal and run pmset -g therm. It reports any thermal warning macOS has recorded.
7 common causes (and fixes)
- An app using lots of CPU. Open Activity Monitor, click CPU, sort by % CPU and quit what's at the top if you don't need it.
- Blocked vents. Beds, cushions and laps block airflow. Use a desk or a firm tray.
- A hot room or direct sun. Sunlight on the lid can heat a laptop fast. Move to the shade.
- Charging while working hard. Charging adds heat. It's safe, but it combines with heavy work.
- External displays and GPU work. Driving big displays, games and video export all load the graphics chip.
- Background tasks after an update. Spotlight (
mds_stores) and Photos (photoanalysisd) catch up for a while, then stop. - Too many browser tabs. A few busy tabs can add up. Close what you're not using, or check the browser's own task manager.
How to cool your Mac down fast
- Quit the busiest app in Activity Monitor.
- Put it on a hard surface with space around the vents.
- Close the lid of a laptop driving an external display only if it's set up for closed-lid use; otherwise leave it open to breathe.
- Turn on Low Power Mode (System Settings › Battery) for lighter tasks. It trades a little speed for less heat.
When heat means something's wrong
If your Mac is hot while idle for days, restart it first. If it stays hot, run Apple Diagnostics: on Apple silicon, shut down, press and hold the power button until the startup options appear, then press ⌘ D.