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Kaspersky Free Anti-Virus: Lean and Mean

Kaspersky Free Antivirus delivers excellent protection with a moderate performance impact, but it has few extra features.

Kaspersky 2020 logo.
Editor's Choice
(Image: © Kaspersky)

Our Verdict

Kaspersky Free Antivirus delivers excellent protection with a moderate performance impact, but it has few extra features.


  • Excellent malware protection
  • Light-to-moderate performance hit
  • Fast scanning
  • Some customization options


  • Bare-bones with few extra features

Kaspersky Free Antivirus 2019 has one of the fastest scanning engines around, plus an ability to customize its defenses and malware protection that's second to none. 

It is bare-bones basic, lacking the items, such as a password manager, hardened browser, firewall or other bells and whistles, that rival brands build their free security software around. Yet despite those shortcomings, we think it's the best free antivirus software out there, especially since it's based on our top pick for the best paid antivirus software.

While Bitdefender Antivirus Free Edition delivers similarly excellent protection and performance along with a minimal set of features, Avast Free Antivirus delivers slightly lesser protection but provides some of the most-wanted extras.

What's Covered and Upgrade Options

The latest edition of Kaspersky Free Antivirus provides basic defenses against online attacks, including a superior malware scanner and protections from dangerous websites, but it doesn't give you much else.

Kaspersky Free Anti-Virus settings page.

Kaspersky's free and paid malware products work with Windows 7, Windows 8.1 and Windows 10, and all share the same malware-detection software. 

After Kaspersky Free Antivirus, the next step up is Kaspersky Anti-Virus, which starts at $40/£24.99 per year for a single computer. It adds more-robust defenses against ransomware, phishing and spyware attacks.

Kaspersky Internet Security, starting at $60/£34.99 per year, expands the coverage to include macOS, iOS, Android and even Windows Phone 8 devices. It thwarts networking threats, can stop dangerous apps from being installed, includes webcam protection and VPN client software, and comes with browser add-ons that rate site safety and can block banner ads.

Kaspersky Total Security starts at $80/£39.99 per year and adds file encryption, parental controls, a password manager and backup software. (Kaspersky makes some of the best Mac antivirus software and best Android antivirus apps.)

A new addition is Kaspersky Security Cloud, an all-encompassing personalized service that spans devices and combines antivirus software, parental controls, identity protection and a VPN service. Its yearly costs range from $90/£49.99 for three devices to $150/£164.99 for a family with 20 devices.

We're aware that Kaspersky Lab has been accused by U.S. politicians of spying on behalf of Russia and has been banned for use by U.S. government agencies and defense contractors. For our part, Tom's Guide has never seen any convincing evidence that Kaspersky products are compromised, and we will continue to recommend Kaspersky products for general consumer use.

Antivirus Protection

Regardless of whether you get Kaspersky Free Antivirus 2019 or one of its paid siblings, the underlying technology uses three levels of protection. First, a file scanner tries to match local items with known threats. Then, heuristic analysis looks for the behavioral clues and other signs associated with malware attack.

Kaspersky Free Anti-Virus settings page.

Finally, the online Kaspersky Security Network examines anything new that looks amiss and issues updates several times a day to the company's 400 million users.

Kaspersky Free Anti-Virus installation pop-up.

The Kaspersky Security Network grabs data from your computer about online destinations and malware threats, but you can opt out of this data collection.

Kaspersky Free Anti-Virus settings page.

You have the choice of three levels of scan intensity and can turn some features on and off. If the scanning is still too much of an annoyance, you can use the software's Gaming mode, which will reduce interruptions during an all-night Fortnite session or on movie night.

Kaspersky Free Anti-Virus external-drive-detection warning.

From the Kaspersky interface's main page, you can start a full-system scan in two clicks. Quick scans are an extra click below the surface. You can right-click on any item in the Windows Explorer to scan that item. Unusually for free antivirus software, Kaspersky Free Antivirus lets you schedule scans and will offer to scan inserted USB drives.

Antivirus Performance

Kaspersky Free Antivirus uses one of the best malware scanners available anywhere and provides better protection than some paid programs. Kaspersky's scanner, shared across its Windows antivirus software, caught just about every piece of malicious code that lab testers threw at it, but it didn't treat safe software as a threat. In other words, Kaspersky strikes the right balance between defense and usability.

Kaspersky Free Anti-Virus running a scan.

In our own lab tests, Kaspersky Anti-Virus (the paid version) caught all browser-borne malware but didn't block every single malicious website, resulting in a score of 98. The software caught all malware samples placed on a computer.

In three recent rounds of bimonthly tests conducted in the first half of 2018 by German lab AV-Test, which exposes the top antivirus products to thousands of pieces of malware, Kaspersky Internet Security's results were so good — perfect, in fact — that they were kind of boring.

Whether running on Windows 7 (January and February) or on Windows 10 (March and April, and then again in May and June), Kaspersky's file scanner stopped 100 percent of widespread, known malware, and the software's heuristic monitoring stopped 100 percent of previously unseen "zero-day" malware.

Kaspersky Free Anti-Virus running a quick scan.

More to the point, the Kaspersky scanner registered no false positives in any of these tests; it didn't mistakenly flag harmless files. This puts Kaspersky's technology half a step ahead of Bitdefender, which also stopped all malware but had a total of 19 false positives over the same three test periods.

In three recent rounds of bimonthly tests conducted by AV-Test, Kaspersky Internet Security's results were so good — perfect, in fact — that they were kind of boring.

Kaspersky performed nearly as well on evaluations conducted by Austrian lab AV-Comparatives, which tests antivirus products against malware found online. 

Over six months, from February to July 2018, Kaspersky Internet Security stopped an average of 99.8 percent of malware and racked up only a single false positive across the entire period. The software's lowest score was 99.5 percent in March, but it got 100 percent in three other months.

Kaspersky Free Anti-Virus installation recommendations.

Avira Antivirus Pro and Bitdefender Internet Security did about as well as Kaspersky at stopping malware, but each got six false positives over those six months. No other product, free or paid, tested by AV-Comparatives came close to Kaspersky's balance of protection and usability.

SE Labs in England runs slightly more-complicated tests, exposing major antivirus products both to known malware and to highly sophisticated attacks of the sort you'd see targeting politicians and diplomats. Kaspersky Internet Security detected all of the attacks but failed to stop one targeted attack (even though the attack was detected), resulting in a score of 99.

MORE: Kaspersky Review: Still the One to Beat

That was the highest score of all the malware-detection engines offered by free antivirus makers. Bitdefender and Windows Defender each got a 96, while Avira and AVG got 94 each, and Avast brought up the rear with 91. (SE Labs did not test Panda.)

Security and Privacy Features

Kaspersky Free Anti-Virus is simple and straightforward while delivering basic malware protection.

While it lacks browser add-ons that rate and block websites by reputation, this type of protection is built in to the program and can stop a phishing attempt before it starts.

Performance and System Impact

Kaspersky Free Antivirus is a good performer with some of the fastest scanning times around, but it uses a light-to-moderate amount of system resources to provide protection.

Kaspersky Free Anti-Virus malware-definition update.

To check the program's impact on overall performance, we used our custom benchmark test, which measures how long it takes to match 20,000 names and 20,000 addresses in an OpenOffice spreadsheet. Our testbed was an Asus X555LA notebook with a 2GHz Core i3 processor, 6GB of RAM and 117GB of files on a 500GB hard drive, running Windows 10 with the latest updates.

Kaspersky Free Anti-Virus notification center.

Before we installed Kaspersky Free Antivirus, the OpenOffice test completed its task in 7 minutes. This time increased to 7:11 with Free Antivirus loaded, but without active scanning taking place. That adds up to a very light passive performance decrease of 2.6 percent, the smallest slowdown we saw among free antivirus programs.

During full scans, the OpenOffice test finished in 8 minutes and 21 seconds, a performance decline of 19 percent from the baseline and 16 percent from no active scans running. That's smack in the middle of the seven free antivirus programs we tested; AVG AntiVirus Free's full scan was the lightest, with an 11 percent slowdown from the baseline, and Avira Free Antivirus was the heaviest, with a 35 percent performance hit.  

Kaspersky Free Antivirus' full scans go by in a flash.

Kaspersky Free Antivirus' Quick Scan OpenOffice completion time was 8 minutes and 13 seconds, a decline of 17 percent from the baseline and 14 percent from pre-scanning results. That's a bit on the heavy side for a quick scan, but was still in the middle of the pack; Avira and Avast Free Antivirus did worse.

Kaspersky Free Antivirus' full scans go by in a flash. The first one took 36 minutes and 39 seconds to look at 333,402 files, but that completion time dropped to a superfast 3 minutes and 29 seconds on the third pass — quicker than some other programs' quick-scan times. Kaspersky Free Antivirus completed a Quick Scan in 2 minutes and 27 seconds.


Kaspersky Free Antivirus' user interface is identical to to those of Kaspersky's paid versions, except that tasks and features that you haven't paid for are covered by a small yellow shield. For instance, there are live links for Scan and Database Update, but Safe Money, Privacy Protection and Parental Controls are not available.

Kaspersky Free Anti-Virus interface dashboard.

Overall, the look is bright and open. When things are safe, the main screen has a green monitor with a check mark that turns yellow when you need to update the program and red when you're potentially under attack.

The Settings button lets you set up or turn off Kaspersky's malicious-tools defense. Some individual features, like File and Web Anti-Virus, Network Attack Blocker, and System Watcher, are locked on.

Kaspersky Free Anti-Virus scan scheduler.

More Tools leads to Security (Cloud Protection, Quarantine and the on-screen keyboard), but My Network, Manage Applications, and Clean and Optimize are grayed out. Still, Kaspersky Free Antivirus offers more customization potential than Bitdefender' Antivirus Free Edition.

Scans can be scheduled daily, weekly or monthly, and you can decide whether to ignore items such as system memory, email archives, boot sectors and networked drives.

You can see which version of the program and viral definitions are being used by hovering the mouse pointer over Kaspersky's Task Tray icon. Give it a right-click, and you can update the definitions, pause the protection or open Settings.

Installation and Support

Installing Kaspersky Free Antivirus on our PC took 4 minutes and 50 seconds. The initial 2.5MB beachhead program lets you pick a language and opt out of data collection. Then, the 138.5MB main installer is downloaded and runs automatically. At the end, you choose whether you block adware and other identity-related threats.

Kaspersky Free Anti-Virus installation progress bar.

Support and help are limited to what Kaspersky offers online: a deep knowledge base, troubleshooting tips, and a thorough glossary of current threats and terms. You won't get any personalized attention via email, phone or chat, though.

Bottom Line

Kaspersky Free Antivirus offers the basics and little else, but its thorough malware scanner does a better job than many paid applications. It's got a very light background performance impact and a moderate one during full scans.

If you're looking for more features, consider Avast Free Antivirus, which has a password manager and hardened browser, but at the cost of inferior malware protection. If you want something that's even more bare-bones, but with equally good malware protection, try Bitdefender Antivirus Free Edition.

Credit: Tom's Guide