How to Limit Windows Defender CPU Usage

In this tutorial, we are going to see how to limit Windows Defender CPU usage. When scanning, Windows Defender uses up to 50% of your processor power. If necessary, you can set explicit limits. Follow the steps below to set the maximum CPU usage limit for Windows Defender.

Windows Defender runs in the background and provides real-time protection from any type of virus, malware, or potentially unwanted program. Sometimes it also performs an automatic scan to make sure your computer is not infected.
 

 

Method 1: How to Limit Windows Defender CPU Usage Using PowerShell

Using a single PowerShell command, you can limit Windows Defender CPU usage on your system. All you have to do is open the PowerShell as an administrator and run the command.
 
Step 1: Press Windows + X button and select Windows PowerShell (Admin). This is the fastest way to open the PowerShell as an administrator.
 

 
Step 2: In the PowerShell window, run the command below but replace <percentage> with the actual percentage between 10 and 100. For example, you want to limit CPU usage to 25%, type “25”.

Set-MpPreference -ScanAvgCPULoadFactor <percentage>

 
If you ever want to reset this setting, simply run the above command while replacing <percentage> with 50. As, 50% is the default CPU usage limit for Windows Defender.
 

 

Method 2: How to Limit Windows Defender CPU Usage Using PowerShell

If you don’t like the command line method, you can use the Group Policy Editor to do the same thing. Keep in mind that this tool is only available in the Pro and Enterprise versions. If you are using the Home edition, follow the first method.

Step 1: Right-click on the Start button, select Run.
 

 
Step 2: Type gpedit.msc and press Enter to open the Local Group Policy Editor.
 

 

 
Step 3: After that, navigate to the following path:

Computer Configuration -> Administrative Templates -> Windows Defender Antivirus -> Scan

Find and double-click the Specify the maximum percentage of CPU utilization during a scan policy.
 

 
Step 4: In the properties window, select “Enabled” and then enter the percentage between 10 and 100 in the Options section. Click the Ok button to save the changes.

Note: If you set the percentage to “0”, it will completely disable CPU limitation for Windows Defender, allowing it to use as much as it wants.
 

 
Now restart Windows to apply the policy to your system.
 
That’s All!