Private and open-source alternatives to Microsoft Defender Antivirus
3 anti-malware rated against the same public privacy criteria as Microsoft Defender Antivirus (Windows Defender), with our picks first.
Why look for an alternative?
- Open source: no. Closed source.
- No trackers or telemetry: partial. Reports on suspected malware and file samples are sent to Microsoft by default; this reporting can be turned off.
- Independent audit: no. No independent audit is published.
See the full Microsoft Defender Antivirus rating.
The alternatives
ClamAV Grade C
Open-source antivirus engine for detecting viruses, malware and other threats on Linux, macOS and Windows, maintained by Cisco Talos.
Based in the United States (Five Eyes). ClamAV scores 65 out of 100 (grade C) on the anti-malware criteria. It meets 2 of 4 criteria: open source and no ads or data sales.
Bitdefender Grade F
Antivirus and security software from Romania for Windows, macOS, Android and iOS, with web protection, a VPN and anti-theft features.
Based in Romania. Bitdefender scores 20 out of 100 (grade F) on the anti-malware criteria. It meets 1 of 4 criteria: no ads or data sales.
ESET Grade F
Antivirus and security software from Slovakia for Windows, macOS, Linux and Android, including the NOD32 antivirus engine.
Based in Slovakia. ESET scores 20 out of 100 (grade F) on the anti-malware criteria. It meets 1 of 4 criteria: no ads or data sales.