Why is my Mac running hot, and what can I do about it?

First, is it actually too hot?

A MacBook that feels warm on the bottom while you work is normal. An Apple Silicon chip under sustained load can reach the 90s °C internally, and that’s within design. It’s a problem when:

• It’s hot while you’re doing nothing.
• Fans run loudly for a long time on light work.
• Things get noticeably slower after a few minutes of load. That’s thermal throttling.
• Your Mac shows a warning or shuts down.

Typical ranges are in normal Apple Silicon temperatures. For how to read the sensors, see check your Mac’s temperature.

Find what’s heating it

Heat is power, and power is work. Find the work:

top -o cpu -l 2 -n 10 -stats pid,command,cpu,power

Or open Activity Monitor and sort the CPU tab by % CPU, then the Energy tab by Energy Impact. Don’t forget the GPU: Window › GPU History in Activity Monitor shows whether graphics is busy, which a CPU list won’t show.

The usual heat sources on a developer Mac:

Source	How to spot it
A build, test run or bundler	node, swift-frontend, clang, cargo, rustc near the top
Docker containers	com.docker.virtualization or Virtualization.VM; check docker stats
A local LLM	ollama or llama-server, plus high GPU in GPU History
Browser tab	Chrome or Safari helpers; use the browser’s task manager
Background indexing	mds_stores, mdworker, photoanalysisd
External displays	WindowServer busy, especially at high refresh rates

If kernel_task is high while the Mac is hot, that’s macOS cooling itself by keeping CPU time away from apps. It’s the effect, not the cause. See kernel_task.

Cool it down

Start with the workload, then the environment:

1. Stop what’s busy. Quit the app, close the tab, or stop the container. A forgotten npm run dev or test watcher can keep a chip warm all day.
2. Give it air. On a MacBook Pro, the vents are along the back and sides. Don’t use it on a bed, a couch or your lap with a blanket. A hard surface or a stand helps.
3. Watch the room. Direct sun and hot rooms make a big difference, especially for fanless Airs.
4. Charge smarter. Heavy work while fast charging from low adds heat. If you can, let it charge before a long render.
5. Lower the load. Close high refresh rate external displays you aren’t using, lower brightness, or turn on Low Power Mode in System Settings › Battery. Low Power Mode caps performance and heat.
6. Clean the vents. On older MacBook Pros, dust in the vents raises temperatures. A soft brush on the outside is safe; opening the case isn’t something to do casually.

What doesn’t help much: cooling pads on a MacBook Pro (the vents aren’t on the bottom), and “RAM cleaner” or “CPU optimizer” apps, which add work instead of removing it.

MacBook Air: no fan, different behavior

Apple Silicon MacBook Airs are fanless. They get hotter under long loads and then slow down to stay safe. For short bursts they’re as fast as a Pro; for 20-minute builds or renders they settle to lower speeds. That’s by design. If you regularly run long, heavy jobs, a MacBook Pro or Mac mini with fans will sustain higher speeds.

When to worry

Contact Apple or a repair shop if the Mac shuts down from heat, the bottom is too hot to touch at idle, the battery case looks swollen (trackpad clicks feel stiff, the case doesn’t sit flat), or fans run at full speed constantly with nothing busy. That last one can be a sensor or firmware issue. Apple Silicon has no separate SMC reset: shut down fully, wait 30 seconds and start up again, which does the same job.

Seeing it live

Stat Space can show temperature in the menu bar, and the popover adds power in watts for CPU, GPU and Neural Engine, plus fan speed. The System tab has a thermal pill (Cool, Warm, Hot · throttling) and a hot-Mac notice, and Home’s Power & heat card plots watts against temperature, so you see which app’s spike lined up with the heat. Temperature alerts are free.

On Macs with fans, an optional helper lets you set fan speed by hand or with a temperature curve. Pro’s spike rewind records the top three processes each time temperature crosses your threshold.