Avast Free Antivirus tops our rankings due to its solid detection and friendly interface; Avira AntiVir Personal is a close second, however, on the strength of its malware detection and removal. Edited by Nick Mediati Avast Free Antivirus 5 Avast Free Antivirus is a well-rounded free antivirus package: It does a solid job at blocking malware, has a pleasant interface, and scans files quickly.