Antivirus free edition limitations

The free AVs often provide a bare minimum protection level, compared with the paid AVs, but some have additional features that are usually found only in the paid versions. Some free AVs have more advertising, with popups to upgrade to a paid version. Paid versions typically have additional, more comprehensive tools like identity theft protection, firewalls, parental controls, and system performance tools. Some paid versions do a better job of detecting malware, but the differences are usually small, like 96% compared with 95.7% of the samples. The biggest disadvantage with the free ones is the lack of customer support. Avast offers email support for free users. Some only offer a knowledge base or a forum section to ask questions.

The best free AVs for overall performance are Avast and Avira Antivir. The overall best paid AVs are Norton and BitDefender. You really need to review the features of each antivirus to determine what is best for you.