Though some newer MacBooks are exceptions, the majority of Mac computers have cooling fans. Still, processors and other electronic parts all generate heat when they’re used. And the more you use them, the hotter they get.
Most of the time, you won’t even notice the fans running. They usually hum along quietly in the background. But do something more demanding like video editing, and they may start to spin faster, making more noise in the process.
Sometimes, though, they’re excessively noisy, or they might kick in when you’re not doing anything with your Mac. In that case, you might be wondering why your MacBook fans are going crazy.
In this guide, we look at some of the potential reasons for loud fans in a Mac, as well as things that might fix the problem. Of course, we can’t know for sure why your particular Mac is having problems with its fans, so it’s worth working your way through these tips.
Before we start:
Sometimes, problems with third-party software can cause your Mac to overheat. It’s a good idea to make sure all your apps are up-to-date, and MacKeeper can help with its Update Tracker feature.
Here’s what to do:
- Download our app and launch it.
- Select Update Tracker in MacKeeper’s sidebar.
- Click Scan for updates.
- Select all apps you want to update and click Update.
In this article you will find the following:
Why is your Mac fan so loud?
I’ve experienced issues with my Mac fan on a few occasions, and it’s not just an annoyance. In some cases, this problem can result in my computer overheating—putting it at a bigger risk of malfunctioning.
Some of the main reasons why your fan might be so loud are:
- Your vents are blocked: Beds, cushions, and other objects might block your Mac vents.
- Dust and debris: If you haven’t cleaned your Mac in a while, dust and debris could stop the fan from working.
- CPU usage: Demanding programs, such as video-editing software, will make your Mac fan need to work harder.
- Ambient temperature: Your device’s temperature can dictate how loud the fan is.
- Hardware problems: A loud Mac fan is sometimes the symptom of more complex issues with your computer hardware.
- Malware: If your computer has malware, it’ll need to work twice as hard to operate normally.
How to stop MacBook fan noise
To tackle this problem, I’ve done multiple things in the past. I recommend starting with the more simple solutions before then moving on to the complex one if needed.
Below is a full list of solutions for stopping your MacBook fan noise:
- Check your Mac’s vents aren’t blocked.
- Clean dust out of your Mac.
- Stop processes with high CPU usage.
- Free up memory on Mac.
- Bring down the ambient temperature.
- Check for hardware problems.
- Reset your Mac’s SMC.
- Check for malware.
- Check for macOS updates.
1. Check your Mac’s vents aren’t blocked
One of the most common reasons why a MacBook Air fan is so loud all of a sudden is that it’s blocked. The same goes for the MacBook Pro.
The fans in your Mac work by pushing warm air out and pulling fresh air in. If any of the vents are blocked, that can’t happen, so your Mac keeps getting hotter — and the fans keep speeding up to compensate.
This happens a lot with MacBooks when users place them on soft objects like beds or cushions. So if your MacBook is running loudly, try moving it to a hard, flat surface, like a table or desk.
With all types of Macs, you should also make sure the vents aren’t clogged up with anything. If they are, use a brush to clean them out.
2. Clean dust out of your Mac
One of the big problems with fan-based cooling is it draws in dust as well as air. Over time, that builds up and sits on the motherboard and components like a blanket. Removing this dust can stop your Mac overheating and producing loud fan noise. If you own a Mac Pro, you can simply pop off the side and clean it out, but you can’t do that with other models.
What you can do is get a can of compressed air and try to blast some of the dust out. A vacuum cleaner could also do the trick but be careful, especially if you have a powerful vacuum cleaner.
3. Stop processes with high CPU usage
When your Mac’s processor is under high load, it'll heat up. The more it has to do, the hotter it'll get. Using the Activity Monitor app, you can stop your Mac’s loud fan noise by shutting down whatever is making your processor work so hard.
To stop processes with the macOS Activity Monitor:
- Go to Applications > Utilities, and open Activity Monitor.
- In the CPU tab, click the top of the % CPU column to sort by highest first.
- If anything is using an excessive amount of CPU time, select it and click the X button.
- Click Quit to shut the process down.
4. Free up memory on your Mac
Freeing up memory on my computer is one of the easiest ways I solve numerous problems, including issues with my MacBook Pro fan being too loud. Apple has some helpful tools to assist with this, such as storage space optimization and automatically emptying the Trash folder. However, I also like to see if there are any applications consuming too much space. Outdated apps are a big culprit for this.
Here’s how I free up memory on my Mac:
- Navigate to the Apple menu and select System Settings when the dropdown menu appears.
- Go to General > Storage.
- At the top of the next window, you’ll see a bar showing you everything that’s consuming your storage. Assess to see what needs to be deleted.
- Start by optimizing storage space and automatically emptying your Trash.
- Go into each category (e.g. Applications and Documents). Highlight everything you don’t need and select Delete. I recommend looking for easy things to remove, such as apps you don’t use, big documents, and downloaded podcast episodes that you’ve listened to.
5. Bring down the ambient temperature
It might seem obvious, but if you’re in a hot room, your Mac will be hot too. In our experience, that could be enough to make it spin up its fans and start making a noise.
The fix is quite simple: bring down the temperature in the room by opening a window or lowering your heating. You could also aim a desk fan at your Mac to help it cool down.
6. Check for hardware problems
Faulty components can sometimes produce excessive amounts of heat. But that’s not the only potential hardware problem — Macs have several heat sensors inside them, which tell the fans when to spin faster. If these sensors break down, that could also cause your Mac’s fans to spin faster and louder.
Using macOS’s built-in Apple Diagnostics, you might be able to find the source of the issue. However, there are no guarantees that this will work.
Here’s how to run Apple Diagnostics on an Intel Mac:
- Turn on your Mac, then press and hold the D key.
- Keep holding it until a list of languages.
- Pick a language, and Apple Diagnostics will run automatically, spitting out a result at the end.
On an M1 Mac, you can run Apple Diagnostics like this:
- Turn on your Mac by pressing and holding the power button.
- Release the power button when you see the startup options.
- Now, press Cmd + D to load Apple Diagnostics.
7. Reset your SMC
Resetting the System Management Controller (SMC) will fix many problems on your Mac, especially if you have an Intel-based computer. The SMC controls not just your MacBook fans, but also the power supply and lighting. So, I recommend restarting this feature if you’re still encountering problems with your device after trying each step above.
The process to reset your SMC will differ depending on whether your Mac has an Intel or Apple Silicon chip. Here’s how to reset the SMC on an Intel desktop computer made in 2018 or later:
- Turn off your Mac and unplug the power cord.
- After 15 seconds, plug the power cord back in.
- Then, after another five seconds, turn your Mac on again.
If you have an Apple Silicon MacBook, you just have to turn off your computer and wait for around 30 seconds. Once you’ve done that, switch it back on. Your SMC issues should now be solved.
For other Mac models, you can check out this comprehensive guide on resetting your Mac SMC.
8. Check for malware
Malicious software can do a couple of things that make your Mac’s fans run constantly or louder than normal. It can increase load on your processor, which will cause excess heat. Or it can take direct control of your fans. In fact, it’s been shown that hackers could modulate fan vibrations to transmit information through sound waves.
You can scan for malware using MacKeeper like this:
- In MacKeeper, select Antivirus from the sidebar.
- Click Start Scan.
- Let the scan run.
- If it finds anything, select it and click Move to quarantine.
Related reading: How To Remove Viruses and Malware From Your Mac
9. Check for macOS software updates
An overheating fan could also be the result of not updating your Mac software. This has happened to me numerous times, and it has even bigger risks beyond a noisy fan. I always keep my macOS software updated because it protects me from security threats. Having access to the latest Mac features is a nice extra bonus, too.
Apple releases software updates throughout the year, in addition to its major ones every fall. Sometimes, macOS might not automatically update—even if you have these switched on. So, it’s worth checking manually. Here’s how:
- Go to System Settings > General and select Software Update.
- Wait to see if Apple has an update available. If it does, click on Update Now.
- Enter your password if needed and confirm that you agree with Apple’s licensing agreement.
- Wait for macOS to update. Then, sign into your account with your normal login details.
A note from our experts: We recommend ensuring that you’re connected to a speedy Wi-Fi connection to ensure that macOS updates without too much of a delay. Be sure to confirm that you have enough storage space so that Apple can download the software onto your device, and expect your computer to restart multiple times.
What to do if your Mac’s fans still won’t turn off
If your Mac is overheating or if the fans are loud even when it’s cold, it could have a more serious problem. That could be software or hardware related. In the case of faulty hardware, there’s little you can do except try to get it repaired. Contact Apple support or a qualified repair service, and they will likely be able to help you.
Usually, though, when a Mac’s fans are making a lot of noise, the solution is simple. Hopefully, one of our tips here will do the trick for you.
FAQ
1. What will happen if my Mac’s fans stop working?
If your fans stop working completely, your Mac will just keep on getting hotter and hotter. Eventually, it'll shut itself down to stop components being permanently damaged. This can also happen if your Mac’s vents are blocked.
2. Can I control my Mac’s fans manually?
By default, no. Your Mac will spin your fans as fast as it thinks it needs to in order to stay cool. You can, however, download software that lets you control your Mac’s fans manually. If you know what you’re doing, this can be useful, but it’s also risky — which is why we’re not recommending any fan control solutions here.
3. How much heat is normal?
Macs can generate a lot of heat and still operate safely. For example, Apple says the normal operating temperature of a MacBook is between 50ºC and 95ºC. So don’t worry if your Mac feels warm when you’re using it.
Read more:
