Microsoft Defender scored 17.5 out of 18 in the June 2026 evaluations by AV-Test, while Avast Free Antivirus and AVG AntiVirus Free both achieved a perfect score of 18 out of 18. Avira Internet Security scored 16.5. The evaluations assessed 16 consumer antivirus products based on protection, performance, and usability. Microsoft Defender is built into Windows 11 and is free, while Avast and AVG are true free offerings. AV-Test uses a scoring system where each category is scored out of 6.0, leading to a maximum total of 18.0. Users should ensure they have the latest versions of antivirus products and only run one real-time antivirus engine at a time. Common pitfalls include running two real-time engines and downloading from unofficial sources. For low-risk users, Microsoft Defender is sufficient, while those seeking higher protection may consider Avast or AVG.