NetBalancer is a free tool for Windows that allows you to monitor network traffic for individual applications. In addition, you can measure and limit data usage and bandwidth of specific apps.

Heavy data usage

If you sometimes wonder why you reached the data limit of your mobile Internet plan, even though you are sure that you didn’t download big files or use bandwidth-intensive applications, you need a tool that tells you which application actually used up all your data allowance. NetBalancer can do just that, and more. This free network traffic monitor also allows you to restrict the heavy data usage of an application.

Monitor network traffic with NetBalancer

Monitoring network traffic with NetBalancer

The ability of Windows 8.1 to handle metered Internet connections is very limited. If you set a WiFi connection to “metered” (right-click the connection), Windows will restrain itself a little.

Set as metered connection

Set as metered connection

For instance, the OneDrive settings enable you to determine what kind of data is synced with the cloud if you are on a metered connection. You can also configure whether Windows will download new drivers (PC Settings > PC and Devices > Devices) over a metered connection.

A few applications exist that notice if you are on a metered connection. Outlook, for instance, will warn you and will only connect to Exchange if you give your confirmation. This has a reason. Outlook is a real bandwidth hog. In my case, my wondering ended after I monitored my network traffic with NetBalancer.

Outlook metered network warning

Outlook metered network warning

Outlook is constantly syncing data even if you don’t send emails or modify entries. If you keep Outlook running continuously, you might use up 1 gig of data within a day. Note that I hadn’t added any significant amount of data to my mailboxes in months. Depending on your data plan, you might reach your limit just by running Outlook for a couple of hours a day. It is amazing that, despite Microsoft’s new “mobile first” mantra, one of its most important Internet application is not yet mobile ready.

Monitor network traffic

However, Windows wouldn’t be Windows if there wasn’t an application that helps you solve the problem. After you launch NetBalancer, you will get an overview of the applications that use Internet connections. In NetBalancer’s main window, you see their current bandwidth usage and how much data they downloaded or uploaded since you started Windows.

If you want to get an overview of the data usage for a certain time period, you can use NetBalancer’s Traffic Chart. First, you have to select Traffic Chart on the Window menu. Next, on the View submenu of the Traffic Chart menu, you can set the time period. Then, you have to click the Traffic Chart icon in the lower left corner of the traffic monitoring tool. The lower pane will then display a data usage chart and table for the selected time period. You will also see how much data all your applications consumed. If you hover your mouse over the time scale, NetBalancer displays how much each app consumed on the specific date.

Traffic Chart’s overview of the monthly data usage per application

Traffic Chart’s overview of the monthly data usage per application

Limit bandwidth of a program

After you find the culprit, you can easily restrict the amount of data that the application can cut out of your limited data plan. The simplest way is to limit the bandwidth usage of the application. For instance, I observed that Outlook syncs data at rates of 1 KB/s to 100 KB/s. After I configured a rule that restricted Outlook to 5 KB/s, the synced data stayed within reasonable limits and I could still send and receive emails. Below this rate, Outlook sometimes disconnected from Office 365.

To restrict an application in NetBalancer, you have to create a rule for the application. To do so, right-click the application and choose Create Rule. Next, you have to change the Download Priority and Upload Priority to Limited and then specify the corresponding rates. Note that, because of a bug in NetBalancer, if you enlarged the Windows font size, you might not be able to edit the bandwidth settings. I had to change my font size to 100%. Also note that, when I set the priority to Custom, Outlook often had problems connecting to Exchange and complained with the strange message “Allow this website to configure email address server settings.”

Limit bandwidth of a program

Limit bandwidth of a program

Limit data usage of an application

Another way to restrict an application is to limit the amount of data that it can download or upload. The section below “Select the traffic amount condition when this rule becomes active” allows you to set a data usage limit for a specific time period. If you want to ensure that the application doesn’t exceed this limit, you have to set the Download Priority and Upload Priority to Blocked. Of course, you can also just restrict the download and upload speed once the data limit is reached.

Limit data usage of a Windows application

Limit data usage of a Windows application

It is also possible to limit the data usage of Windows as whole—that is, for all applications. For this, you have to create a NetBalancer rule without specifying a particular application. To do so, click the Edit menu, and then navigate to Rules. Next, you have to add a new rule that sets the Download Priority and Upload Priority to Blocked once the traffic of this rule reaches your data usage limit within the configured time period.


NetBalancer has quite a few additional features that I didn’t cover in this post. Its original purpose was to set download priorities for applications. With the high-speed networks we have today, this functionality is probably no longer a priority (sorry for the pun). However, in a server environment this feature could still be useful. You can also set network filters and get an overview of the IP addresses your applications are connected to. I was quite surprised that Windows Explorer connected to several servers in Singapore. It turned out that these servers were operated by Microsoft. Yes, the cloud now covers the entire planet.

The free version of NetBalancer is limited to a maximum of three process priorities/limits and three rules at a time. If you want to restrict more applications, you have to shell out $50. I think the price is justified. Perhaps you can switch to a cheaper data plan after you find and restrict all your heavy bandwidth consumers. The only feature I really miss is the ability to configure data usage limits depending on whether I am on a metered connection or not. If you want to lift the restrictions, you have to disable the corresponding NetBalancer rule manually.

1 Comment
  1. Peter Steier 8 years ago

    Unfortunately, NetBalancer breaks the connectivity of my unbranded Huawei 3131 and Austrian yesss! SIM.

Leave a reply

Please enclose code in pre tags

Your email address will not be published.


© 4sysops 2006 - 2023


Please ask IT administration questions in the forums. Any other messages are welcome.


Log in with your credentials


Forgot your details?

Create Account