Antivirus & Internet Security
Best Free Antivirus in 2026: Solid Protection for $0
The best free antivirus options for Windows, Mac and Android — what you get, what's held back for paid users, and privacy questions to ask before installing.
You don't need to pay to be protected. The free options below provide real-time protection; paid upgrades mostly add extras like VPNs, firewalls and identity monitoring.
Our picks at a glance
No paid rankings · prices not shown (they change often)
- 1Microsoft Defender AntivirusBest built-in option for Windows
- 2BitdefenderBest free third-party protection
- 3AviraBest free extras
- 4Avast Free AntivirusMost popular free suite
- 5MalwarebytesBest free second-opinion scanner
The best free antivirus
Microsoft Defender Antivirus
Best built-in option for WindowsDetails pending editor verificationThe antivirus built into Windows 10 and 11 at no extra cost.
What we like
- Included with Windows — nothing to install
- Real-time protection, firewall and ransomware folder protection
- Updated automatically through Windows Update
Watch out for
- No bundled extras like a VPN or password manager
- Windows-focused; other devices need separate protection
Free option: free plan
Visit official site for Microsoft Defender Antivirus (opens in new tab)Official websiteBitdefender
Best free third-party protectionDetails pending editor verificationSecurity suite that regularly ranks among the top performers in independent lab tests.
What we like
- Strong results in AV-TEST and AV-Comparatives programmes
- Multi-layer ransomware protection
- Suites for Windows, Mac, Android and iOS
- Free edition available for Windows
Watch out for
- Bundled VPN has a daily data limit on standard tiers
- Renewal prices are higher than first-year offers
Avira
Best free extrasDetails pending editor verificationFree antivirus from Gen Digital that bundles a few privacy tools.
What we like
- Free antivirus with real-time protection
- Free tier includes a limited VPN and other tools
- Light interface
Watch out for
- Free tools are limited and push upgrades
Avast Free Antivirus
Most popular free suiteDetails pending editor verificationPopular free antivirus from Gen Digital with optional paid upgrades.
What we like
- Free real-time antivirus for Windows, Mac and Android
- Wi-Fi network scanner
- Paid tiers add firewall and more
Watch out for
- In 2024 the US FTC took action against Avast over sales of browsing data via a former subsidiary — review privacy settings
- Free version shows upgrade prompts
Free option: free plan
Check current pricing for Avast Free Antivirus (opens in new tab)Official websiteMalwarebytes
Best free second-opinion scannerDetails pending editor verificationWell-known malware remover with a free on-demand scanner and a paid real-time edition.
What we like
- Free scanner is a popular second-opinion cleanup tool
- Premium adds real-time protection
- Simple interface
Watch out for
- Free version has no real-time protection
Free antivirus checklist
- Turn on automatic updates for your operating system and browser.
- Install only one real-time antivirus — two can conflict.
- Review privacy settings and opt out of data sharing where offered.
- Use a password manager and two-factor authentication.
Frequently asked questions
Is free antivirus safe?
Free antivirus from well-known vendors provides genuine real-time protection. Read the privacy policy and adjust data-sharing settings, since free products may rely on upgrades or data to fund themselves.
Can I run two antivirus programs?
Run only one real-time antivirus. You can safely use an on-demand scanner like Malwarebytes Free alongside it for occasional second-opinion scans.
Editors & researchers
Our editorial team researches, tests and fact-checks every guide. Articles are reviewed against our editorial policy before publishing and re-reviewed on a schedule.
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