When it comes to antivirus protection you want a company with experience. Avira has been around for 25 years, which is about as long as PC viruses have existed. The company's principals want everyone to be safe from malware, so they give away Avira Free Antivirus 2012 (free, direct) for non-commercial use.

Avira can't survive just by giving away free protection, of course. Commercial users must purchase the paid edition, and those using the free product are encouraged to upgrade to Avira's full security suite. In fact, the free antivirus's main window includes all the same components as the full suite, with the unavailable ones tantalizingly grayed out.

Good Lab Results
All of the independent labs I follow test Avira's technology with the exception of West Coast Labs. ICSA Labs certifies Avira for virus detection and removal. In both the on-demand and retrospective tests by AV-Comparatives.org, Avira took the top rating, ADVANCED+. And in all of the last ten tests by Virus Bulletin, Avira received the VB100 award for complete success.

AV-Comparatives also runs a dynamic whole-product test, challenging multiple products to defend against real-world malicious attack over a period of weeks. In this test Avira rated ADVANCED, the second highest rating.

Every two months AV-Test.org releases antivirus certification results based on real world testing under Windows 7, Vista, or XP. Products can earn up to six points for protection, remediation, and usability, with a total of 11 required to pass. Like BullGuard and Trend Micro, Avira averaged 12.5 points in the latest three tests. Bitdefender's average of 16.33 is currently the best. For more details on what these tests mean, see How We Interpret Antivirus Lab Tests.

Avira Free Antivirus 2012 lab tests chart

Good Malware Cleanup
Avira installed without incident on my twelve malware-infested test systems. The antivirus runs a quick scan for active malware immediately upon installation. This scan caught quite a few threats and required a reboot on most of the test systems. One even needed a second reboot.

A full scan of my standard clean test system took 20 minutes, a bit below the average. However, a second scan came in only a couple minutes shorter. AVG Anti-Virus Free 2012 (Free, 4 stars), Norton AntiVirus 2012 ($39.99 direct, 4.5 stars), and others cut the time for a repeat scan by 90 percent or more.

Avira's real-time protection also nabbed a few of the threats. By default it simply blocks access to the threat and asks for permission to fully remove it. When you grant permission it runs a mini-scan to detect related malware traces. A couple of the test systems had three or more of these mini-scans running at once, making for a very busy desktop. I'm not complaining; if the system is badly infested with malware the antivirus should be busy.

After running a complete scan on all of the test systems I tallied up the results. Avira detected 88 percent of the threats, the same as AVG. It scored 6.7 points for malware cleanup overall, a bit better than AVG's 6.5.

In the breakout test looking specifically at scareware, Avira detected all the threats and scored 9.5 points. That's exactly the same as AVG, Norman Malware Cleaner 2.1 (Free, 3.5 stars), and Panda Cloud Anti-Virus 1.5 Free Edition (Free, 3.5 stars). Of recent free antivirus products, only Malwarebytes' Anti-Malware Free 1.51 (Free, 4 stars) did better, scoring a perfect 10.

Avira didn’t do as well against threats using rootkit technology. It detected 86 percent of those and scored 5.0 points. AVG and Panda detected 100 percent and scored 6.7 points and 4.1 points respectively. The champion against rootkits is Norton, which detected 100 percent and scored 8.9 points. To fully understand the source of these scores, see see How We Test Malware Removal.

Avira Free Antivirus 2012 malware removal chart

Good Malware Blocking, Too
I started my examination of Avira's real time protection by attempting to re-download my current malware collection. Of the still-valid URLs, Avira blocked 36 percent  in the browser. It blocked another 29 percent earlier or later during the download process, depending on when it recognized the threat. That's decent, but Trend Micro Titanium Antivirus+ 2012 ($39.95 direct, 2.5 stars) blocked 89 percent of this same collection and TrustPort Antivirus 2012 ($39.95 direct, 3.5 stars) blocked 93 percent.

I continued by opening a folder containing already-downloaded malware samples. Avira blocked just under two-thirds of these samples right away. Each time it detected a few it asked permission to remove them and then launched a mini-scan. At one point I had five mini-scans running simultaneously. However, these scans finished quickly and correctly determined that these never-launched samples had not planted any additional malware traces.

I launched those samples that survived the initial shootout and recorded how Avira handled them. It detected 91 percent of the threats, the same as Norton and lower than AVG's 94 percent. However, with 8.7 points overall Avira beat AVG's 8.4. Norton scored 9.0 points on this test, and Webroot SecureAnywhere Antivirus ($39.95 direct, 4.5 stars) beat all the rest with a perfect 10 across the board.

Like Panda Cloud, AVG, and quite a few others, Avira detected 100 percent of the rootkit samples. Its blocking was mostly effective, though one rootkit managed to install and activate its stealth technology. Even so, Avira scored 8.7 points for rootkit removal. Panda and AVG beat that with 9.3 points; Norton and Webroot aced this test with a perfect 10 points.

Most of the current collection of antivirus products have detected 100 percent of my scareware samples; Avira is no exception. Its score of 9.8 points in this test would be impressive but for the fact that Norton, Webroot, Malwarebytes' Anti-Malware PRO 1.51 ($24.95 direct, 3 stars), and others scored a perfect 10. For details on how I derive these scores, see How We Test Malware Blocking.

Avira Free Antivirus 2012 malware blocking chart

In both the malware cleanup and malware blocking tests, Avira's one weak spot involved rootkits. Despite its blocking efforts, one rootkit managed to install completely, and in the cleanup test a couple of the rootkit samples were still running after Avira's supposed removal. In all other areas it fared much better.

Avira's "Advanced Heuristic Analysis and Detection" (AHeAD) feature is designed to detect threats missed by ordinary signature-based detection. This kind of technology can sometimes flag valid programs as well. For a quick sanity check I installed 20 PCMag utilities that hook deeply into Windows.

AHeAD didn't flag any as suspicious, which is good. However, Avira's signature-based detection erroneously identified one utility as WORM/Bancodor.U.3. The utility does install a global Windows keyboard hook, so an antivirus might be forgiven for suspecting it of being a keylogger. Calling it a worm seems very strange.

Antiphishing Bonus
The Web protection that blocks access to known malware-hosting sites is also designed to keep users away from fraudulent (phishing) sites. I tested it using URLs that had been very recently reported but not yet verified as fraudulent.

My results suggest that Avira relies too strongly on databases of known phishing sites and doesn't handle freshly-minded frauds well. Almost 60 percent of the sites that it did block had already been shut down. Since those now-absent sites pose no danger of fraud, they don't count as successful detections.

I use Norton as a touchstone for antiphishing tests because it blocks both known fraudulent sites and unknown sites that it detects using heuristic techniques. Avira's detection rate was 82 percentage points lower than Norton's and 11 percentage points behind Internet Explorer alone. The article How We Test Antiphishing explains exactly how I derive these scores.

Avira Free Antivirus 2012 antiphishing chart

Phishing protection is simply a bonus, so I don't count this result against Avira overall. The product also offers an Avira-branded Ask toolbar that also reports the status of your Avira installation.

A Good Free Choice
Avira Free Antivirus 2012 performed very well in my hands-on testing. It also gets good ratings from the independent testing labs. Most of its scores in my testing were quite close to those of AVG Anti-Virus Free 2012 (Free, 4 stars), PCMag's current Editors' Choice for free antivirus. Avira even edged out AVG in some tests, but its weakness against rootkits leaves AVG in the top spot.

Even so, both products are free for non-commercial use, so you can give both a try. If Avira suits you better, go for it!

More Antivirus reviews: