Earlier today, AV-TEST, which is a reputed anti-malware assessment firm, released its latest rankings for anti-virus products for home users. This was the first time that AV-TEST evaluated the performance of such products on a test bench running Windows 11. And surprisingly, the overall performance of Microsoft Defender turned out to be far worse than expected. In fact, it only managed to secure the last place where it shared the position with another product. This is quite contrary to how Defender generally does on Windows 10 in AV-TEST's assessments.
The findings of AV-TEST seem to match AV-Comparatives' latest test results as well. In the case of the latter, Microsoft Defender was found to bog down a user's system the most (according to a quantitive metric) out of all the tested products. File copying, archiving, and app installations seem to be the Achilles' heel of Defender as they have the greatest performance impact according to AV-Comparatives' test, and once again, it is in line with what AV-TEST also found, and extremely similar results were also seen in AV-Comparatives' own previous ranking.
AV-TEST graded the different anti-virus products using its own AV-C or AVC score as well as a PCMark score. The AVC score has the full mark of 90 while the PC Mark score is out of 100. The total performance impact is indicated by the Impact Score and it is obtained by subtracting the total score obtained by the product out of 190. So the lower the Impact Score, the better. Microsoft comes in last place here with 27.7 points as it obtained the highest Impact Score.
In case you are wondering how the AVC score was derived, AV-Comparatives explains:
For the AV-C score, we took the rounded mean values of first and subsequent runs for File Copying, whilst for Launching Applications we considered only the subsequent runs. “Very fast” gets 15 points, “fast” gets 10 points, “mediocre” gets 5 points and “slow” gets 0 points.
Finally, we have the certifications and as expected, Microsoft received the Standard rating here, which is the lowest rank. It wasn't alone though as Total Defense also received the same certificate as it was just a little bit ahead of Defender in the Impact Score (table in the image above).
You can find AV-Comparatives' full test report here.