Bitdefender, Norton Top Mac OS X Antivirus Test Ratings

Whether you agree or disagree with its rankings, few companies test security products as assiduously (and as regularly) as AV-TEST. Its latest round of Mac OS X security-suite testing, the results of which were released this morning (Dec. 17), demonstrated mostly promising results. 

Of 13 popular antivirus programs, eight received perfect scores when it came to security detection, and we can consider these to be the best Mac antivirus software products. Only three programs failed outright. Gauging system performance, however, was a little trickier.

AV-TEST, a Madgeburg, Germany-based independent testing lab, rates security programs for Windows, Mac, Android, Linux and mobile platforms on a regular basis. We use their tests to gauge the best antivirus software and best Android antivirus apps.

This latest round of program testing evaluated 13 different programs for OS X, both free and paid, to see how well they detected potential online threats, as well as how much of an impact they had on a computer's other processes. While Macs are still not quite as susceptible to attacks as Windows machines, this is an issue of scale, not of architecture. More people use Windows machines, and so more criminals target them.

The eight OS X antivirus programs with perfect malware-detection scores were Avast Mac Security 2015 11.3, Avira Free Antivirus 3.2, Bitdefender Antivirus for Mac 4.0, ESET Endpoint Security 6.1, Kaspersky Internet Security 15.0, SentinelOne 1.6, Sophos Anti-Virus 9.4 and Symantec Norton Security 6.4.

Of particular interest here is SentinelOne, a new Israeli security firm: its product, designed for enterprise use, does not check malware against a database of digital signatures, but rather uses only behavior-based detection. Most other antivirus products do both, but signature-based detection has become less efficient as more malware learns to change shape to avoid it.

On the other end of the spectrum were F-Secure Anti-Virus 15.4 (with a 76.2 percent detection rate), Webroot SecureAnywhere 8.0 (78.6 percent detection rate) and ClamXav 2.8 (88.1 percent detection rate). AV-TEST deemed these programs failures for scoring below a 90 percent detection rate. Panda Antivirus 10.7 and Intego Mac Premium Bundle X8 10.8 scored between 90 and 100 percent, getting passing, but not enthusiastic, grades.

In terms of system performance, however, only four programs did extremely well: ClamXav, Panda, Symantec and Bitdefender. These programs each took between 62 and 64 seconds to copy 26.6 GB of data (while scanning it, of course), 9 seconds apiece to calculate MD5 checksums (which give files unique identifiers) and about 90 seconds apiece to download test files. Each one slowed down the Mac OS by 10 percent or less during security operations.

Beyond that, every program slowed down the system by at least 20 percent (Sophos and ESET fell into this efficiency range). SentinelOne slowed down the system by 80 percent, while Avast, despite its stellar security features, clocked in at a staggering 170 percent. (AV-TEST noted that Avast automatically scanned files as they were still downloading, while the rest did so after a download had completed.)

Norton and Bitdefender appear to offer the best mix of security and efficiency, but as long as you have some computing power to spare, any of the eight perfect programs should make your Mac a safer place to work. Otherwise, try to run your system scans when you're off doing something else.

Marshall Honorof

Marshall Honorof is a senior editor for Tom's Guide, overseeing the site's coverage of gaming hardware and software. He comes from a science writing background, having studied paleomammalogy, biological anthropology, and the history of science and technology. After hours, you can find him practicing taekwondo or doing deep dives on classic sci-fi.