We have found several antivirus programs with such a low system slowdown that you only notice them when you do something that is CPU intensive, such as: Playing a high-end game or rendering videos. If you want anti-virus software not to slow you down, these are the programs to buy and avoid.
The simplest antivirus we tested was Bitdefender Total Security Key, which slowed down our test laptop by 7.7-17% during active scans. Bitdefender is also one of our recommendations for the best overall antivirus.
The lightest free antivirus was AVG Free Antivirus, which had a 5-11% system impact.
How we test the performance impact of audiovisual software
During the summer, we tested 12 free and paid Windows antivirus programs on an Asus X555LA laptop. We measure the speed of the system before installing any third-party antivirus. after an antivirus program has been installed, but not during active scans; during a full scan; and during a quick scan. Each test was performed three times for each program and the results were averaged.
Neither Bitdefender nor AVG were the fastest in the three categories we measured: Passive System Impact, Full Scan System Impact, and Rapid Scan System Impact. However, they both ranked first or second out of the three, while most other shows were less consistent in their rankings.
You will probably notice this slowdown even if you were just checking your emails. You wouldn’t notice Bitdefender hitting 17% if it weren’t using a lot of CPU.
Furthermore, Panda Free Antivirus (7.4%) had a slower scan slowdown than AVG (10.3%). However, Panda’s slowdown on the full scan was in half at 23%, while AVG’s was less than half at 11%.
It ranked second among paid antivirus programs. Kaspersky Total Security ranked third in all three test categories, although Bitdefender fought other programs first.
There were some free programs that worked fine, but we couldn’t run all the tests on them.
Microsoft Windows Defender had the second smallest impact in the full scan and the third smallest in the quick scan. However, it is built into Windows 10 and will work automatically if you don’t have a third-party antivirus. So we couldn’t really measure the impact on the bottom. However, we can assume that this will have less impact than most other programs.
Bitdefender Antivirus Free Edition came in second for passive and comprehensive scanning purposes, but it does not offer a quick scan. However, AVG made or beat it in the other categories.
Most antivirus brands offer three or four different paid Windows programs, all of which offer the same basic protection, but add a few more features with each price increase.
For example, Bitdefender offers Bitdefender Antivirus Plus, Bitdefender Internet Security, and Bitdefender Total Security, each costing around $ 20 more a year than the last. But only the latter has all the bells and whistles Bitdefender offers, such as a password manager, webcam protection, parental controls, or a system optimizer. When deciding which antivirus to buy, evaluate which one has the features you need.