Is Microsoft Defender enough? Free vs. paid antivirus
Windows 10 and Windows 11 come with Microsoft Defender Antivirus included at no extra cost. The right question is not “do I need antivirus?” but “do I need anything beyond what I already have?”.
Products with a higher rate in the same test
- Kaspersky — 99.8% (399/400)
- Bitdefender — 99.5% (398/400)
- Norton 360 — 99.3% (397/400)
- Avast Premium Security — 99.3% (397/400)
- AVG Internet Security — 99.3% (397/400)
The difference between 99.0% and 99.8% is 3 attacks out of 400. A single test does not tell the whole story: results vary from round to round, so it is worth following several reports over time, on AV-Comparatives and AV-TEST.
When Defender is enough
- You use a single Windows PC that you keep updated.
- You don't need a VPN, password manager or parental controls in one bundle.
- You are careful about what you download and about links received by email or message.
When a paid antivirus is worth it
- Several devices and systems: Android phones, Macs, the family's PCs — one subscription and one account.
- Included extras: many bundles include a VPN, password manager, identity protection or cloud storage. Check what each plan includes in the comparator.
- Support: a paid product comes with help from the vendor.
Whatever you choose
Keep Windows and your browser updated, use a different password for every account and two-factor authentication. No antivirus stops 100% of attacks — not even in tests.
See the full tableFrequently asked questions
Is Microsoft Defender a good antivirus?
In the AV-Comparatives Real-World Protection test of Feb–May 2026, Microsoft Defender blocked 396 of 400 attacks (99.0%). The highest rate was 99.8% (Kaspersky).
Do I need antivirus if I have Windows 11?
Windows 11 includes Microsoft Defender Antivirus. A paid antivirus makes sense if you want protection for several devices and systems or extras such as a VPN and a password manager.