MacBook Overheating? How to Find the Cause and Cool It Down

MacBook overheating almost always comes from one of three things: a process keeping the processor busy, a browser full of active tabs, or heat that cannot escape through the vents. The quickest check is to open Activity Monitor, click the CPU tab and sort by % CPU. Whatever sits at the top is usually the culprit, and quitting or calming it cools the Mac within a few minutes.

A warm MacBook is normal. A MacBook that is hot to the touch while you are only reading email, with the fans roaring or the system stuttering, is not. This guide starts with the 60-second check, then walks through the causes from most to least common, each with its fix, and ends with habits that stop the heat coming back. It applies to macOS 26 Tahoe, macOS 15 Sequoia and macOS 14 Sonoma on both Apple Silicon and Intel MacBooks.

The 60-second check in Activity Monitor

Before you change any settings, find out what is actually generating the heat. Activity Monitor tells you in under a minute.

Press Command-Space, type Activity Monitor and press Return.
Choose View > All Processes so system processes are listed too.
Click the CPU tab, then click the % CPU column header until the busiest process is at the top.
Watch the CPU Load graph at the bottom of the window for 30 seconds. If it stays high while you are doing nothing demanding, something in the background is working hard.
Click the Energy tab and check the Energy Impact column and the Preventing Sleep column.

How to read the numbers

Short spikes are normal. A process that stays above roughly 80 to 100% CPU for minutes is the kind that heats a MacBook. Values above 100% are possible because each processor core counts as 100%, so 250% means the process is keeping two and a half cores busy.

On Intel MacBooks you may see kernel_task using a lot of CPU. Do not try to quit it. Apple documents this as macOS deliberately occupying the processor so other processes cannot heat it further. It is a symptom of heat, not the cause, so look at the next process down the list.

Is the Mac already throttling?

Open Terminal and run pmset -g therm. If it reports a thermal or performance warning level, macOS is already limiting processor speed to manage temperature. That is protection, not damage, but it explains why a hot Mac also feels slow.

Common causes of MacBook overheating, ranked

These are ordered from the causes we see most often to the rarest. Work down the list and stop when the heat stops.

1. A runaway app or background process

An app stuck in a loop, a sync client re-uploading a folder, a container engine, a video converter or a misbehaving plugin can hold a core at 100% for hours. This is the single most common reason a MacBook runs hot while idle.

Fix: in Activity Monitor, select the process, click the Stop button (the X in the toolbar) and choose Quit. Use Force Quit only if Quit does nothing. If the same app keeps returning to the top, update it, check its settings for background sync or indexing options, or remove it from System Settings > General > Login Items so it stops starting with the Mac.

2. Browser tabs that never stop working

Every open tab can keep running scripts, ads, video and live updates even when you are not looking at it. Dashboards, chat apps, design tools and social feeds are the usual offenders. In Activity Monitor, Chrome-based browsers show up as many Helper (Renderer) processes, and Safari shows Web Content processes labeled with the site name.

Fix: in Chrome, open Window > Task Manager to see which tab or extension is using the CPU, then close it or end the process. Turn on Memory Saver in Chrome under Settings > Performance so inactive tabs are discarded. Disable extensions you do not use, since some run on every page. Keeping fewer tabs actively loaded is one of the easiest ways to cut background heat.

3. Indexing, photo analysis and sync after an update

After a macOS update, a migration to a new Mac or a big photo import, macOS rebuilds its indexes. Processes such as mds_stores, mdworker, photoanalysisd, cloudd, bird and backupd can keep a MacBook warm for hours.

Fix: plug the Mac in, leave the lid open and let it finish. This work is temporary. If Spotlight never settles, add large folders that do not need searching, such as virtual machine images or build folders, to the Spotlight privacy list in System Settings.

4. Low memory and heavy swap

When apps and tabs need more memory than the Mac has, macOS compresses memory and writes the overflow to the SSD as swap. Constant compressing and swapping is extra work for the processor and the disk, and that work turns into heat.

Fix: open the Memory tab in Activity Monitor. If the Memory Pressure graph is yellow or red and Swap Used keeps growing, reduce what is open at once. Our guide Why Is My Mac So Slow? covers memory pressure in more detail.

5. Blocked vents and a hot room

MacBooks with fans pull air in and push it out through openings near the hinge and along the edges. A bed, sofa cushion, blanket or your lap can block them. Apple recommends using Mac notebooks at ambient temperatures between 50 and 95 degrees Fahrenheit (10 to 35 degrees Celsius), so direct sun or a hot car pushes any Mac toward throttling.

Fix: use a hard, flat surface. A simple stand that lifts the back improves airflow and gets the bottom case off the desk. Never run a demanding task with the Mac inside a bag or sleeve.

6. Charging, external displays and clamshell mode

Charging a low battery while you work hard adds heat from the battery itself. External displays add graphics work, which shows up as higher CPU for WindowServer. Running the Mac closed in clamshell mode removes the keyboard area as a surface that sheds heat.

Fix: do heavy work after the battery has some charge, or keep the lid open on a stand when you use external displays. If WindowServer stays high, close windows you do not need and try System Settings > Accessibility > Display > Reduce transparency.

7. Dust, a failing fan or a swollen battery

Older Intel MacBooks can collect dust in the fan and heat sink over years of use, and fans eventually wear out. A battery that has swollen can lift the trackpad or bottom case and is a reason to stop using the Mac and get it serviced.

Fix: run Apple Diagnostics. On Apple Silicon, shut down, press and hold the power button until startup options appear, then press Command-D. On Intel, restart and hold the D key. For cleaning, fan replacement or battery issues, book an Apple Store or Apple Authorized Service Provider appointment rather than opening the case.

Heat that is expected

Gaming, exporting video, compiling large projects and running local AI models will heat any MacBook. Fanless MacBook Air models stay silent and slow down instead of spinning a fan, so a warm bottom case during an export is normal there.

Fixes that do not cool a MacBook

Some popular advice treats the symptom rather than the cause.

Fan-control apps can make fans spin sooner, which adds noise, but they do nothing about the process creating the heat.
Memory "cleaners" that only purge RAM free memory for a moment. If a tab or app is still busy, the CPU work and the heat continue.
Restarting helps for a while because it stops everything, but runaway apps and heavy tabs come back once you reopen them.
Cooling pads help a little on hot days. They cannot keep up with a process stuck at 100%.
Putting the Mac in a fridge or freezer risks condensation inside the case. Do not do it.

On Intel MacBooks, Apple suggests resetting the SMC when fans behave oddly, such as running at full speed with no load. Apple Silicon Macs have no SMC reset; a shutdown and restart covers the same ground. If you are weighing a cleanup app, our comparison of the best Mac cleaner apps explains which tools address which problems.

How Mac Ninja keeps background heat down

The causes above share a pattern: something you are not using keeps working. Quitting it works, but you usually want that app or tab back later. Mac Ninja is a menu bar app built for exactly that situation, and it never closes your apps or your normal tabs.

Foreground Boost moves background apps that hog the processor or the disk while you work into macOS's own low-priority lane. They get full speed back the instant you switch to them. It adapts to battery, Low Power Mode and heat, and while nobody is at the Mac the calmed apps catch up at full speed.
Idle tab unloading in Google Chrome, Brave, Microsoft Edge, Arc, Vivaldi, Opera, Comet, Dia, Chromium and Safari (Safari in Lite mode). Tabs untouched for 15 minutes, adjustable in Settings, are unloaded, sooner when memory is tight. They stay in the tab strip and reload when clicked. The visible tab, pinned tabs, incognito windows and tabs playing sound are skipped.
Live stats for heat and power, CPU load, memory pressure and swap, the three heaviest apps by CPU and disk, apps idle for hours holding memory, and apps keeping the Mac awake.
"Why does my Mac feel slow right now?" gives a plain-English reading of the live numbers, phrased by Apple Intelligence's on-device model on macOS 26 and later, so nothing leaves the Mac.

It never slows apps that are playing or recording audio, installs no kernel extensions, changes no system files and has no account or tracking. The optional free Mac Ninja Helper extension uses Chrome's native tab discarding and also closes tabs that AI browser agents such as Claude in Chrome leave behind in their own tab groups, after the agent session has been idle for 8 hours. Setup steps are on the support page.

Who it is not for

Mac Ninja cannot clear dust from a fan, replace a swollen battery, unblock a vent or make an old processor faster, and it cannot fix a full disk. If the heat comes from a game or an export you are actively running, that work is in the foreground and should run at full speed. It is for the most common case: a MacBook that runs hot because of background apps and tabs.

How to stop MacBook overheating from coming back

Once the Mac has cooled down, a few habits keep it that way.

Check Activity Monitor weekly, sorted by % CPU, and deal with anything that sits at the top for no reason.
Trim System Settings > General > Login Items so only apps you need start with the Mac.
Keep Chrome Memory Saver on, or let a tab unloader handle idle tabs across all your browsers.
Remove browser extensions you have not used in a month.
Keep macOS and your apps updated, since runaway processes are often fixed in updates.
Use the Mac on a hard surface, ideally raised at the back, and out of direct sun.
On battery, set System Settings > Battery > Low Power Mode to Only on Battery to cap heat and extend runtime.
Restart every week or two so leaked memory and stuck processes are cleared.

What to do next

Open Activity Monitor now and sort by % CPU. If one app or a pile of browser tabs is at the top, you have found your heat source. Quit what you do not need, and if you want background apps calmed and idle tabs unloaded automatically without losing anything, try Mac Ninja free for 7 days. Plans are $9.99 per year or $24.99 once for up to 3 Macs, with a 14-day money-back guarantee; see pricing. If Apple Diagnostics reports a fan or battery fault, book a repair instead, since no app fixes hardware.

Frequently asked questions

Is it normal for a MacBook to get hot?

Yes, within limits. A MacBook gets warm during video calls, exports, games and while charging, and the bottom case can feel hot under heavy load. It is not normal for the Mac to run hot while you only browse or write. In that case, open Activity Monitor, sort the CPU tab by % CPU and look for an app or tab that stays busy in the background.

Can overheating damage a MacBook?

macOS protects the hardware by slowing the processor and spinning the fans when temperatures rise, and it will shut the Mac down if heat becomes extreme. Normal warmth does not cause damage. Long-term heat can age the battery faster, though, and a swollen battery is a real problem. If the trackpad or case starts lifting, stop using the Mac and have it serviced.

Why does my MacBook get hot when charging?

Charging generates heat in the battery, and that heat adds to whatever the processor is producing. A low battery charging quickly while you run demanding apps is the hottest combination. Let the Mac charge during lighter work, keep it on a hard surface with the vents clear, and check Activity Monitor for background apps that keep the processor busy at the same time.

Do Apple Silicon MacBooks overheat?

Apple Silicon MacBooks run much cooler than older Intel models, but they still heat up under sustained load. The fanless MacBook Air does not spin a fan; it slows the processor instead, so overheating shows up as sluggishness. MacBook Pro models ramp their fans. Runaway processes, busy browser tabs and blocked vents cause heat on Apple Silicon just as they do on Intel.

Does Mac Ninja lower my Mac's temperature?

Mac Ninja reduces background work, which is the most common source of unnecessary heat. Foreground Boost moves CPU- and disk-hungry background apps to macOS's low-priority lane, adapting to heat, battery and Low Power Mode, and idle browser tabs are unloaded. It shows heat and power in its stats. It cannot fix dust, a failing fan, blocked vents or a game you are actively playing.