Bitdefender Antivirus Free was upgraded to version 27.0.62.355 on September 11, 2026, introducing a new Advanced Threat Defense driver that enhances behavioral monitoring capabilities. The free version is designed for Windows only and promises to remain free indefinitely, lacking features found in paid versions such as anti-tracking tools and a full vulnerability scanner. The installation requires Windows 10 or 11, at least 2GB of free disk space, a local administrator account, an active internet connection, and a Bitdefender Central account. Users must remove any existing antivirus software before installation, and the installation process typically takes 60 to 75 minutes. Bitdefender Free covers one Windows device and offers robust malware detection capabilities, particularly with the Advanced Threat Defense layer. It is recommended to schedule regular scans and check the Notification Center for quarantined items. If uninstalled, the dedicated uninstall tool should be used to avoid leftovers that could interfere with future installations.