What is the best free antivirus?
The short answer
Microsoft Defender is the best free antivirus for most people. It offers top-tier protection, comes already installed and never tries to sell you anything. If you want a free suite on top, Avast One Essential is the best and includes a VPN allowance. AVG and Avira are solid alternatives.
In detail
The best free antivirus is the one you already have. Microsoft Defender scores with the best in independent tests. It works with the ransomware folder protection and SmartScreen in Windows. It is also the only free option that never tries to sell you anything mid-scan. Turn on automatic updates and controlled folder access for a genuinely strong baseline.
If you want more than the baseline without paying, try Avast One Essential. It adds a real suite around the engine. You get the same engine as paid Avast, basic privacy tools and 5 GB of VPN per week. That is the most generous free package available. AVG Free and Avira Free are fine substitutes. AVG shares Avast’s parent company and engine. Avira comes with a handy software updater. All three suggest upgrades from time to time. That is part of how free software is funded.
Paid suites earn their keep for some people. Think of anyone who manages a family’s devices or runs a business from their PC. The same goes if you want phishing protection at full strength. Free antivirus offered through a popup or a cold call is not real antivirus. It is malware with a logo.
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