Avira, Bitdefender, Kaspersky Top Antivirus Test Results

The time has come again for AV-TEST, a German firm that periodically evaluates antivirus programs, to share its results for Windows 8.1. For longtime followers, the outcome is not shocking: Avira, Bitdefender and Kaspersky Lab achieved perfect scores, while Microsoft's built-in Windows Defender scraped the bottom of the barrel once again.

Evaluations conducted by the Madgeburg, Germany-based independent lab measure the effectiveness of Windows, Android and Mac antivirus software for home and corporate users. The current crop of AV-TEST results comes from measurements taken in May and June 2015, and rates each program based on standards of protection, performance and usability. A program could earn up to six points in each category.

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Perfect scores of 18 went to Avira Antivirus Pro 2015, Bitdefender Internet Security 2015 and Kaspersky Lab Internet Security 2015. (AV-TEST evaluates those products submitted to it by vendors; most vendors have more than one product, but each malware engine should be the same across a single vendor's Windows product line.) Running the programs has a negligible effect on a computer's performance, and each one is very simple to navigate.

Competing products from Ahn Lab, F-Secure, G Data, McAfee, Microworld, Norton Symantec and Trend Micro also scored perfect sixes in the malware-protection category, though were less than perfect in at least one of the other two categories. All provided complete or virtually complete protection from "widespread and prevalent" malware well known to antivirus vendors, as well as "zero-day" malware discovered within the four weeks before testing.

Fourteen out of the 21 programs tested scored either 99 or 100 percent in both categories. (At Tom's Guide, we use AV-TEST's malware-protection scores for our own reviews of antivirus software; however, we run our own performance tests and usability assessments.)

On the other end of the spectrum, Microsoft Windows Defender was in a category all its own, scoring only 9.5 out of a possible 18 points. The program earned an ignominious half-point in the protection category, blocking only 89 percent of existing threats and 95 percent of new ones. It also scored a mere 3 in performance, having consumed a lot of system resources, although it was extremely user-friendly, earning a perfect six points in usability.

Other poorly performing programs included ThreatTrack VIPRE Internet Security 2015, Quick Heal Total Security 16.0, and ESET Smart Security 8.0, which scored 12, 13.5 and 14 points, respectively, making them comparatively weak choices.

While AV-TEST does not advocate purchasing or avoiding any programs in particular, the results suggest that some programs are, indeed, safer than others. The salient point is that the built-in Microsoft software does not provide adequate protection for most users. Whatever antivirus program you choose, you probably shouldn't use Windows Defender as your first line of defense.

Marshall Honorof is a senior writer for Tom's Guide. Contact him at mhonorof@tomsguide.com. Follow him @marshallhonorof. Follow us @tomsguide, on Facebook and on Google+.

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  • Skylyne
    Avira doesn't perform so well with the testing that AV Comparatives does. If you look at each individual test, you'll see Avira is genuinely lacking. In fact, with my personal method of selecting an AV, Avira didn't make it into the top five, I believe (based solely on protection).

    I was looking at AVC's mobile AV test results, though, and I ended up getting AVL. AVL and Avira differ by only 0.1% for protection testing, but I like the AVL app better. I have Avira's optimiser, though ;)

    People need to remember one important thing about mobile and computer security: the protection will always vary from week to week, month to month, and it will rarely be the same software for both computer and mobile. Can't stress that one enough. I'd have to look deeper into things, but I would definitely consider just using the best for each device, instead of bundling protection.
  • Paul NZ
    Doesnt matter if they come 1st, 2nd 3rd, last most of them crash
  • Skylyne
    Paul, I'm starting to wonder if the real common denominator here is you, and not the AVs lol. I've had to deal with crashing AVs a number of times, but not on my personal computers. Not ever, no matter how bad the computer might have been infected. Before I really got involved in security, I used to go to places that were heavy with malware, and I've never had a problem with an AV crashing. I see it a lot on other computers, but I have no idea how they get it to happen.

    Since it rarely happens in lab testing, I always have to chalk it up to user error. As I explained in another thread (that you're taking part in), it isn't really the fault of the software lol. Yes, it seems to be quite common, but you can't really blame the software...