Macs are well-known for being truly reliable machines. Even when a given Mac can’t get the latest software update because it’s too old, the underlying hardware might still chug along peacefully. Sometimes you can see 10-plus year MacBooks perfectly capable of doing lots of lightweight tasks, like checking email and browsing the web.
Occasionally, our Macs need to do some heavy lifting. For example, when it comes to web development, photo retouching, and video editing. We can tell the work is hard by hearing our MacBook Pro fan controller springing into action and the MacBook Pro fan noise rising. And we’re not surprised.
What actually perplexes us is MacBook fan noises with no apparent reasoning behind them — such as when you’re watching a movie or replying to someone in the chat and suddenly hear your MacBook fan running loudly. If you notice it happening more or less regularly, you should investigate to avoid overheating your Mac.
What Makes Your Mac Overheat
Think of your Mac as a machine with lots of built-in workflows. One of those is using some hardware resources, like CPU, RAM, and SSD, to efficiently solve the tasks at hand and then using your MacBook Air fan to cool those hardware resources down, since they tend to heat up from working out, just like you do while exercising.
A bit of occasional heat is normal — your Mac is designed to handle it. But when you start hearing the MacBook Air fan noise all the time, your machine might overheat, which could happen either because what the tasks you’re throwing at it are too hard for your CPU and RAM to handle or because your MacBook fan control system is not working properly.
Overheating is dangerous as it’s essentially a downward spiral — your CPU and RAM get hot because they can’t process the workload, which makes them even worse at processing the workload. In rare cases, sustained overheating could lead to permanent hardware damage, so it’s best to stop it in its tracks early on or take steps to prevent it from happening altogether. Here are a few things you can do.
Check for the latest software updates
Apple is really good at improving the efficiency of its system-level software. So even if there’s some buggy function that drains the power of your Mac at the moment, it’s very likely to be fixed with the next system software update.
To check if there’s a new macOS version available:
Open System Preferences ➙ Software Update
Click Update Now
Follow the installation instructions
In some cases, you could hear your MacBook fan loudly processing an update, which is normal in this case. Hopefully this will stop once the update is installed.
Similarly, if you find that launching a particular app leads to switch fan loud noises, see whether there’s an update for that specific app available, either via the App Store or by checking the app menu from the menu bar.
Ensure proper ventilation
Another important and often overlooked reason for Mac fan noise is not thinking about how all the hot air can quickly escape from your Mac.
Most MacBooks have their main vents in the back, which can get easily blocked by putting the laptop on soft surfaces like couches, blankets, or your lap, resulting in all the heat being trapped.
The solution here is to always make sure your Mac has enough space around it or is at least put on a hard surface, such as a desk. Ideally, you should get a proper laptop stand for your MacBook that elevates it from the surface to get the best circulation possible.
One more reason for poor ventilation is all the dirt and dust that get accumulated on your MacBook Air fans over time. If you’re asking yourself, “Why is my MacBook Pro fan so loud?” — maybe you need to schedule regular inspections to see if the vents are clear on the outside and gently clean them with a microfiber cloth.
When you find your Mac fan loud but not hot, see if you can unscrew and open the back panel of your MacBook. Then carefully clean out all the dust from the fan itself and the area around it.
Quit using heavy apps
If simply working on your daily projects makes your MacBook fan loud, you should break down your workflow to effectively identify the culprit.
Are you using too many apps at once? Do you have your email, browser, Excel spreadsheets, and PDF reader open at the same time? Do you really need to have 15 active Google Chrome tabs right now? Try to focus your attention and close anything you don’t need to preserve your Mac’s resources only for the most daunting tasks.
However, in case your MacBook fan noise starts as soon as you open a specific app, it could be that the software is just too much for your Mac and you’re better off looking for a less demanding substitute. For example, in the design world, Adobe Illustrator or Figma could be replaced with Sketch; for the browser, you could swap Google Chrome for Safari or Firefox; and so on.
Monitor your CPU and RAM usage
Even if some apps that produce MacBook Pro fan noise are quite obvious, your system could also be susceptible to dozens of hidden processes that you might not have heard about, such as various helper apps. To find them, you have to keep your eye on where your Mac’s CPU and RAM actually go:
Launch Activity Monitor from your Applications ➙ Utilities folder
Navigate to the CPU tab
Click the % CPU column to make sure all the processes are displayed in the descending order
Take note of everything that’s taking up lots of CPU power
If you recognize the process and don’t want it to continue, click the Stop button in the top-left corner
Switch to the Memory (RAM) tab and repeat
Note: When you see a power-hogging process you don’t recognize, don’t stop it! It could be necessary for the overall wellbeing of your system. Instead, it’s better to restart your Mac to get it under control.
If your MacBook Air fan noise frequently distracts you, opening and closing Activity Monitor to investigate might not be the best use of your time. You should pick a solution that’s always available and is not only able to show your CPU and RAM stats but also things like precise air flow temperature.
iStat Menus is a professional monitoring system for your Mac that lives in your menu bar and quietly tracks the progress of all the system indicators you could ever need, such as CPU, RAM, sensors, network, disk usage, battery, time, and even weather forecast. Plus, you can customize its functionality to only get updates on the things you care about — in real time!
Run hardware diagnostics
In rare cases when your Mac fan noise becomes a non-stop nuisance, the problem could lie in the fans themselves. To find out if the problem is really with the hardware, you should conduct an Apple Diagnostic test on your Mac:
Disconnect all devices from your Mac
Turn the Mac off
Switch the Mac back on and hold the D key until the language menu pops up
Select the language and wait until the test is complete. The diagnostics should provide you with a reference code for every issue. Make sure to write them down.
Restart your Mac
If the Apple Diagnostics test has found any issues related to the switch fan loud noise, book an appointment at your local Apple Store or a licensed repair center ASAP to fix the problem. You certainly don’t want your fan issue to result in a laptop meltdown.
Keep your Mac optimized
The truth is Macs provide you with a versatile toolkit to fix lots of hardware issues. But, more often than not, this functionality is not user-friendly, hidden behind the CLI of Terminal, and is not easily accessible. So what’s the better way to optimize your Mac?
CleanMyMac X brings every tool available to you in macOS under one intuitive interface. Here you can choose to free up your RAM, flush DNS cache, delete login items, uninstall apps, get rid of useless system junk — all with the single click of a button. What’s more, CleanMyMac X protects you from malware and cares about your privacy, with easy options to delete cookies or browser cache.
As you can see, having your MacBook fan running at maximum speed all the time is not a good idea and there are a few ways to address this problem, from cleaning the ventilation system to monitoring CPU usage with iStat Menus to running Apple Diagnostics to keeping your Mac in its best shape with CleanMyMac X.
Best of all, iStat Menus and CleanMyMac X mentioned above are available to you absolutely free during a seven-day trial of Setapp, a platform with more than 180 Mac apps strategically curated to cover any area of your life, from finances (MoneyWiz) to cooking (MacGourmet Deluxe) to better internet connection (NetSpot). Try them all at no cost today and see which ones you like best!