Best Free Antivirus Software for Windows

Several antivirus vendors make free antivirus software available for home and SOHO users. But how do you choose the best free antivirus? For starters, don't just consult some random Web list advertising the best free antivirus. You need to make sure the free antivirus has been properly tested and is ranked according to its detection and protection capabilities. Remember, the best free antivirus is really only the best if it keeps your computer safe from viruses, spyware, and other malware. Here are the best free antivirus programs for Windows - based on how well they detect and protect.

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Avira AntiVir Personal is not only my personal pick for best free antivirus software, but also the overwhelming choice for best free antivirus by readers. In the 2011 Readers' Choice Awards, a whopping 62% of voters selected Avira AntiVir Personal as their personal favorite for best free antivirus. Avira AntiVir routinely nabs some of the highest scores from and other antivirus testing agencies. More »

AVG Free Edition is a classic, one of the longest running free antivirus packages available for Windows XP/2000/NT/ME/98. Installing only 30Mb of files and 4 running processes, AVG Free Edition is the smallest antivirus scanner we've tested and may well be the best free antivirus choice for an older PC that has limited system resources. More »

Microsoft Security Essentials earns its spot as one of the best free antivirus as it has consistently performed admirably on third-party antivirus certifications and detection tests. Microsoft Security Essentials is not only free for home use, it's free for small businesses with up to 10 computers to protect. Microsoft Security Essentials runs on XP, Vista, and Windows 7, but can only be installed on genuine Windows installations (i.e. those that are properly licensed). More »

Avast earns its spot as one of the best free antivirus because it not only offers standard scanning, Avast Home Edition also provides scans on bootup. This can greatly increase the chance of removing stubborn infectors, particularly those that use resuscitators to thwart removal attempts. Avast Home Edition supports Windows 95/98/Me, 2000, XP, and Vista. More »

Panda Cloud Antivirus is not only one of the best free antivirus programs, its also the only free cloud-based scanner, Panda antivirus software takes all the processing off your PC, giving you a lighter, faster, and more proactive antivirus protection. Or for for a very low price you can upgrade to Panda Cloud Antivirus Pro and gain additional features as well as 24/7 tech support. More »

Most fo the best free antivirus only provide an antivirus scanner. But what if you need antivirus software and a firewall? Comodo Internet Security was the overwhelming winner of the 2011 Readers' Choice Awards for Best Internet Security Suite. Unlike most free antivirus which is free for home use only, Comodo Internet Security is free for both home and business use - and it even includes 90 days of free tech support. More »