Buying guide · 3 picks
Best free antivirus
Free antivirus is better than its reputation, but each free edition makes a different trade-off. Here is what each one includes, what it leaves out, and which ones the labs actually tested.
Ranked by the AVSO Editorial Desk
Prices and lab results verified How we scoreEditorial policy
Short answer:Avast Free Antivirus. The free edition itself scored 18/18 at AV-TEST and 99.3% at AV-Comparatives. Mind the privacy settings.
Download Avast Free (opens in a new tab)Best free antivirus: our 3 picks, ranked
Top pick Best free antivirus
1. Avast Free Antivirus
Free Antivirus
Why it’s here: The free edition itself scored 18/18 at AV-TEST and 99.3% at AV-Comparatives. Mind the privacy settings.
The evidence
Price
Free (Windows, Mac, Android, iOS)
Download Avast Free (opens in a new tab)30-day money-back guarantee
Best free for Windows only
2. Bitdefender Antivirus Free
Antivirus Free
Why it’s here: Real-time protection and basic ransomware protection on Windows, with a 200 MB/day VPN.
The evidence
- Vendor page · Windows only; lacks full ransomware remediation and anti-tracking3
Price
Free (Windows only)
Download Bitdefender Free (opens in a new tab)30-day money-back guarantee
Best free second opinion
3. Malwarebytes Free
Free scanner
Why it’s here: No real-time protection, but a good on-demand cleanup scan alongside Defender.
The evidence
- Vendor page · Finds and removes existing infections; real-time protection is paid4
Price
Free
Download Malwarebytes Free (opens in a new tab)60-day money-back guarantee
The free antivirus you already have
Microsoft Defender Antivirus is built into Windows 10 and 11 and runs automatically. It was Approved in AV-Comparatives' 2025 summary. Installing another antivirus switches Defender off; uninstalling it switches Defender back on.
A note on Avast and privacy
In June 2024 the FTC finalised an order banning Avast from selling browsing data for advertising and requiring a $16.5 million payment. If that rules Avast out for you, Bitdefender Free (Windows) or Microsoft Defender are the alternatives.
Frequently asked questions
Is free antivirus good enough?
For many people, yes, if it has real-time protection. Avast's free edition scored 18/18 at AV-TEST in August 2026. Paid products add ransomware remediation, firewalls, VPNs and multi-device plans.
Is Malwarebytes Free a real antivirus?
No. It's an on-demand scanner without real-time protection. It's useful for cleanup or a second opinion next to another antivirus.
Top pick · Best free antivirus
Our pick: Avast Free Antivirus
The free edition itself scored 18/18 at AV-TEST and 99.3% at AV-Comparatives. Mind the privacy settings. Free (Windows, Mac, Android, iOS).
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Sources
All accessed
- 1.AV-TEST Windows 11 home-user test, August 2026. av-test.org/en/antivirus/home-windows/windows-11/august-2026/ (opens in a new tab)
- 2.AV-Comparatives Real-World Protection Test, February–May 2026. av-comparatives.org/tests/real-world-protection-test-february-may-2026/ (opens in a new tab)
- 3.bitdefender.com. bitdefender.com/en-us/consumer/free-antivirus (opens in a new tab)
- 4.malwarebytes.com. malwarebytes.com/mwb-download (opens in a new tab)