How We Test Antivirus Software

CNET

17-07-2025

Protecting your devices from viruses and other malware is incredibly important, but effective antivirus detection isn't the only thing to consider when choosing security software. You also want to ensure that the program won't slow your devices down or interfere with everyday tasks. And if you're buying a full cybersecurity suite, you'll need to make sure it covers most or all of your security needs.
Our testing processes are designed to help you find antivirus tools that meet all of these criteria.
Testing environment
All antivirus testing is conducted on a Lenovo ThinkPad with an Intel i5 Processor and Windows 11. Antivirus tools are also installed on a Moto G Stylus 5G Android phone for basic interface testing. Your experience with a specific antivirus may vary based on the devices you're using, especially if you have an older setup.
Browser safety tools are tested on both Chrome and Firefox, with both browsers being updated to the most recent versions before testing. Online tools not directly connected to a browser, such as dark web monitoring, are tested in Firefox.
All tests are conducted by CNET web hosting expert Dianna Gunn, who has 16 years of experience building websites and eight years of experience testing software.
Features
The first stage of testing is evaluating the features associated with the core antivirus and cybersecurity packages offered by the company. We consider both the features of the antivirus itself and the number/types of additional tools available.
We then compare these features with the offerings of top antivirus companies to establish a features rating. Companies with numerous features for both cybersecurity and identity theft protection receive a 10/10 ranking.
Usability
The hands-on portion of testing begins with purchasing a plan, creating an account and testing the following areas of usability:
Account management: How easy it is to access your products, billing and other account management areas
How easy it is to access your products, billing and other account management areas Installation and setup: How fast and user-friendly the installation process is, as well as how easy it is to navigate the core antivirus and the corresponding Android app
How fast and user-friendly the installation process is, as well as how easy it is to navigate the core antivirus and the corresponding Android app Additional tools: How easy it is to install and configure cybersecurity tools bundled with the antivirus, excluding identity theft protection tools
Cybersecurity companies that make all three of these user experiences pleasant and welcoming to folks without technical experience receive a 10/10 usability ranking.
Performance
After installing the antivirus, we run it for two or three days while performing everyday tasks such as surfing the web (with five to seven tabs open) and editing images to get a feel for how the antivirus impacts device performance. We also check Task Manager periodically to see how much processing power (percentage of the CPU) and disk space the program is using.
Over the course of our testing days, we run three of each antivirus scan type offered by the software. This typically includes regular scans, quick scans and deep scans. We time these scans and keep Task Manager open throughout to get a feel for the program's resource usage during scans.
Finally, we move on to testing the additional tools, looking for a few key things:
How quickly online data breach or dark web management tools perform their initial scans, the amount of data they procure within the first scan and the tools they provide for removing or protecting your data
How fast and efficient performance tools are, as well as how effectively they identify areas for improvement
How much browser safety tools impact the browsing experience
Whether scam detection tools flag links from spam folders as suspicious
How much the VPN reduces internet speed
To receive a 10/10 ranking, all tools must be both fast and efficient, using minimal resources and making minimal impact on existing programs' operation so users can continue performing everyday activities. Information management and device performance tools must also accurately identify issues and provide tools or advice for fixing them.
Security and privacy
CNET doesn't conduct security testing due to concerns about infecting devices on a shared internet connection. Instead, we consider third-party testing from established labs with numerous years of experience testing antivirus software and membership in the Anti-Malware Testing Standards Organization. We primarily focus on test results from AV-Test and AV-Comparatives. We look for security scores of 5.5 out of 6 from AV-Test in the past six months and at least one AV-Comparatives award in the past year.
We also evaluate how the cybersecurity company's additional tools protect users' privacy, with an emphasis on password managers and VPNs. The password manager should use AES-256 encryption and zero-knowledge infrastructure that prevents the company -- or anyone else -- from accessing users' passwords. The VPN shouldn't keep logs of IP addresses or internet activity, and any information it does keep – along with information sent through the VPN -- should use AES-256 encryption.
Next, we analyze the company's privacy policies to determine how much information it collects about customers and what it does with that information. We pay special attention to whether the company shares customer data with third parties, the types of third parties it shares customer data with and when it shares that data. We also note where the company is located and its rules around if and when it shares data with public authorities.
Finally, we research the company's history to learn if it's had any known data breaches. If data breaches have occurred, we consider how long it's been since those breaches, how transparent the company was about what occurred and how proactive the company was about fixing security issues.
Companies can net a security ranking of 10/10 if they have:
Consistent high scores in third-party security testing for at least six months
Extensive privacy protocols for additional tools like the password manager and VPN
Thorough privacy policies that state the company collects only data necessary for product performance
Strict limitations on how and when it shares customer data with third parties, including government authorities
No data breaches within the past five years
A history of handling any past data breaches with transparency and efficiency
Customer service
We explore each company's customer service portal, looking for:
A knowledge base with a prominent search function and links to common categories of questions, like account setup or installation
Videos and images are included in knowledge base articles to make tutorials more accessible to visual learners
Easily accessible live chat, phone and email support, preferably with 24/7 service
We then contact the company through each method of communication to determine how fast and helpful its support representatives are. Companies receive a 10/10 customer service ranking if they provide an extensive knowledge base with significant multimedia content, 24/7 support via all three communication channels (live chat, phone and email), fast response times and helpful support representatives.
Value
After developing a thorough understanding of how the cybersecurity products work and how well the company protects its customers, we return to its website to re-evaluate its pricing plans. This time, we focus on comparing prices and features of the basic antivirus, mid-range plan and highest-tier plan to equivalent cybersecurity packages from popular companies.
Companies with pricing in the average range ($30 to $70 per year for the basic antivirus, $150 to $200 for the mid-range plan and $200 to $250 per year for the highest tier plan) and a full roster of cybersecurity tools, including identity theft protection, will receive a value ranking of 10/10.
Overall ranking
Overall rankings are determined by averaging out subcategory rankings. Antivirus companies with a ranking of 8.5 and above are considered for an Editors' Choice award. Companies with a ranking between 7 and 8.5 are included in best lists with recommendations for specific use cases unless there are significant issues with security or privacy. Companies that don't receive at least a 7 in our reviews are not recommended.