How to Tell if You Have Spyware on Your Computer

Alex Patel

Oct 29 2023

Single article img

The spyware industry costs the US economy billions of dollars per year. Indeed, according to the Consumer Spyware Initiative, around 90% of US home computers have been infected with spyware at some time.

If you think that your computer is “acting strangely” or if you suspect spyware has somehow been installed, there are a few ways to find out.

What is Spyware?

Spyware is “spying software”, and as the name implies, it is software that quietly steals information from your computer via the internet connection. It is usually done for advertising purposes, but poses a great risk of identity theft as well.

Spyware applications are usually in bundles with other software programs that you install, especially free software, and especially from shareware platforms. When spyware is installed on your device. It will usually monitor your activity and send that information to someone else.


How to Detect Spyware

There are several signs to look for that may indicate that there is spyware on your device:

Skype Calls

This is something that a lot of people have experienced – a huge phone bill on their Skype account or all of their credits being used up a lot faster than usual. This could be a sign of spyware and someone else using your account.

Strange Search Results

When you start a search using your browser’s address bar and you see an unfamiliar site instead of your usual search site, this may be a result of spyware.

Anti-Spyware Acting Strangely

If you have anti-spyware installed on your computer, pay attention to how it behaves. Look for support files that are missing, spontaneous shutdowns and crashing, and other strange behavior.

Slow Computer

Is your computer running much slower than usual for no reason? Open the task manager and look at the processes tab to see if there is an unfamiliar process running in the background with nearly 100% of available CPU cycles.

New Files and Items

Have you noticed a new item on your Favorites list that keeps reappearing even after you delete it? What about a shortcut on your desktop or a folder on your hard drive? These things may indicate a problem and a security risk.

Look at Your Router/Modem

From time to time, when you’re not using the computer or downloading anything in the background, take a look at your router or modem. You’ll want to see if the lights are blinking wildly like they would when you’re surfing or downloading files. If they are, this could mean that something is using your internet connection to transfer information, probably spyware.


Toolbars are not your friend in most cases and are usually installed without your permission when you download and install some other free product. If you see a toolbar that you don’t remember installing or have trouble uninstalling one, it may be spyware and you should try to use an antivirus or anti-spyware program to remove it.


Homepage Change

Your browser should not suddenly change its homepage without you doing it manually in the settings. If you suddenly see a different homepage, it is probably spyware.

Popups and Advertisements

Popups and advertisements should not appear outside of your browser. If you are not using a browser and a popup appears, you have spyware.

Removing Spyware

The best way to prevent and remove spyware is to have a good antivirus program installed on your computer.

You can read in-depth reviews and see how our experts rank the best antivirus software here to help you choose.

Top5 Antivirus
Advertiser Disclosure

This website is an informative comparison site that aims to offer its users find helpful information regarding the products and offers that will be suitable for their needs. We are able to maintain a free, high-quality service by receiving advertising fees from the brands and service providers we review on this website (though we may also review brands we are not engaged with). These advertising fees, combined with our criteria and methodology, such as the conversion rates, our team of reviewer's finding and subjective experience and product popularity, impact the placement and position of the brands within the comparison table. In the event rating or scoring are assigned by us, they are based on the position in the comparison table, or according to other formula in the event specifically detailed by us. See our How we Rate page and Terms of Use for information. The reviews, rating and scoring are provided “as-is” without guaranties or warranties regarding the information contained in our website, which shall not be considered as endorsement. We make the best efforts to keep the information up-to-date, however, an offer’s terms might change at any time. We do not compare or include all service providers, brands and offers available in the market.

Contact Us

Our goal is to provide answers to all of your questions so you can make a confident purchasing decision. We welcome your feedback, so please email us at with suggestions and questions. We’d love to hear from you!

Your information will be handled as detailed in our Privacy Policy