For most Windows 10 and 11 home users, Microsoft Defender Antivirus is a sensible free starting point: it is built into Windows Security and scored 17.5 out of 18 in AV-TEST’s August 2026 Windows 11 test. Avast Free Antivirus and AVG Antivirus Free each scored 18 out of 18 in that test. On phones, choose protection by platform: Android security apps can provide mobile-specific protections, while iPhone apps should be judged by features such as anti-phishing or identity monitoring—not by promises of unrestricted device-wide virus scanning.
Which free antivirus should you use on a Windows PC?
If you use Windows 10 or 11 and want straightforward protection at no cost, begin with the built-in Microsoft Defender Antivirus. Microsoft says Windows Security is integrated into both operating systems and includes real-time protection and manual scanning. You can check its status by opening Start > Settings > Privacy & security > Windows Security > Virus & threat protection in Windows 11, or Start > Settings > Update & Security > Windows Security in Windows 10. If another antivirus is installed, Windows may hand off active protection to it.
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Independent Windows tests offer useful comparisons, but they measure specific products under specific conditions. In AV-TEST’s August 2026 consumer test on Windows 11, each product could earn up to six points for protection, performance and usability. The maximum was 18 points; AV-TEST identified scores of 17.5 or higher as eligible for its “TOP PRODUCT” award.
The Tool Desk
Outbyte PC Repair FREERepair Windows errors before they cause bigger problemsFix Now →Outbyte Driver Updater FREEScan for outdated or missing drivers - takes under a minuteDriver Scan →| Product tested | AV-TEST, Windows 11, August 2026 | AV-Comparatives, Windows 11, February–May 2026 |
|---|---|---|
| Microsoft Defender Antivirus (Consumer) 4.18 | 17.5/18: protection 6, performance 5.5, usability 6 | 99.0% in 400 real-world test cases |
| Avast Free Antivirus 26.6 | 18/18: 6 in each category | 99.3% in 400 real-world test cases |
| AVG Antivirus Free 26.6 and 26.7 | 18/18: 6 in each category | 99.3% in 400 real-world test cases |
| Bitdefender Total Security | Not tested as a free edition in this AV-TEST comparison | 99.5% in 400 real-world test cases |
The AV-TEST figures are from its August 2026 Windows 11 consumer test. The AV-Comparatives figures are from its February–May 2026 real-world test, which used 400 test cases on fully patched 64-bit Windows 11. Neither lab result guarantees how a product will perform against future threats. AV-Comparatives reports that AVG and Norton use the Avast engine, so their scores should not automatically be read as evidence of wholly independent detection technology. The AV-TEST result for Bitdefender Total Security is not evidence about a free Bitdefender product.
#1 Best Overall
- SPEED-OPTIMIZED, CROSS-PLATFORM PROTECTION: World-class antivirus security and cyber protection for Windows (Windows 7 with Service Pack 1, Windows 8, Windows 8.1, Windows 10, and Windows 11), Mac OS (Yosemite 10.10 or later), iOS (11.2 or later), and Android (5.0 or later). Organize and keep your digital life safe from hackers
- SAFE ONLINE BANKING: A unique, dedicated browser secures your online transactions; Our Total Security product also includes 200MB per day of our new and improved Bitdefender VPN
- ADVANCED THREAT DEFENSE: Real-Time Data Protection, Multi-Layer Malware and Ransomware Protection, Social Network Protection, Game/Movie/Work Modes, Microphone Monitor, Webcam Protection, Anti-Tracker, Phishing, Fraud, and Spam Protection, File Shredder, Parental Controls, and more
- ECO-FRIENDLY PACKAGING: Your product-specific code is printed on a card and shipped inside a protective cardboard sleeve. Simply open packaging and scratch off security ink on the card to reveal your activation code. No more bulky box or hard-to-recycle discs. PLEASE NOTE: Product packaging may vary from the images shown, however the product is the same.
Is Windows Defender enough?
For a typical home user, Microsoft Defender is a reasonable default if it is active and Windows stays updated. In the cited AV-TEST cycle, its protection and usability scores reached six points, while performance scored 5.5. Avast Free and AVG Free achieved a perfect result in that same test, but a perfect lab score does not by itself establish that either is the better fit for every user. The available test results do not settle current differences in advertising, system impact, or free-tier features across vendors.
Consider a third-party free product if you have a specific need its current free edition demonstrably meets. Check the exact edition and included features on the vendor’s current page before installing; the available comparisons do not establish a complete, region-specific feature list for every provider.
Rank #2
![Norton 360 Deluxe 2027 Antivirus, 5 Devices, Auto-Renews [Download] | Includes Scam Protection, Advanced VPN, Dark Web Monitoring, & PC Cloud Backup](https://m.media-amazon.com/images/I/41IYV5zGyCL._SL160_.jpg)
- ONGOING PROTECTION Download instantly & install protection for 5 PCs, Macs, iOS or Android devices in minutes!
- TOP-PERFORMING VPN Faster speeds, more server locations, and greater connection control to protect your privacy across all your devices, including Smart TVs.
- ADVANCED SCAM PROTECTION Help spot hidden scams online. With the built-in Genie AI assistant, you’ll never wonder if a message or email is suspicious again.
- REAL-TIME PROTECTION Advanced security protects against existing and emerging malware threats, including ransomware and viruses, and it won’t slow down your device performance.
- DARK WEB MONITORING Identity thieves can buy or sell your information on websites and forums. We search the dark web and notify you should your information be found.
Do you need antivirus on an Android phone?
Android security is not simply Windows antivirus in a smaller form. Google Play Protect and optional Android security apps are relevant choices, but compare evidence gathered on Android rather than relying on a Windows lab score. AV-Comparatives’ Mobile Security Review 2026 tested the latest apps it obtained from Google Play in May 2026 on unmodified Android 16. Products included Google Play Protect & OS Features 50.9, Avast One Free 26.6 and AVG AntiVirus Free 26.6. That identifies the test platform and versions; it is not a ranking of every free Android app, and the results should not be treated as iPhone evidence.
Do these 3 things before closing this tab:
1Repair Windows errors before they cause bigger problems2Fix the driver behind crashes, sound loss and screen glitches3Clear out junk files and repair common Windows errors- Install apps through Google Play and check the developer, requested permissions and current free-tier terms.
- Use Android-specific test results when comparing mobile protection; do not infer phone performance from Windows scores.
- Keep Android and installed apps updated, and be cautious about links, downloads and permission requests.
Do iPhones need antivirus?
Do not expect a third-party iPhone app to inspect other apps or scan the entire device like a conventional Windows endpoint antivirus. Microsoft documents anti-phishing and identity-monitoring features for its iOS offering; its consumer anti-malware support information lists Windows, Mac and Android, not iOS. Microsoft also explains that iOS security settings prevent one app from seeing the URL another app is opening. These platform boundaries are why iPhone security apps should be assessed by the specific features they offer, such as web protection, phishing warnings, identity monitoring or scam alerts.
Rank #3
![Norton 360 Premium 2027 Antivirus, 10 Devices, Auto-Renews [Download]](https://m.media-amazon.com/images/I/41JNWru8mYL._SL160_.jpg)
- ONGOING PROTECTION Download instantly & install protection for 10 PCs, Macs, iOS or Android devices in minutes!
- TOP-PERFORMING VPN Faster speeds, more server locations, and greater connection control to protect your privacy across all your devices, including Smart TVs.
- ADVANCED SCAM PROTECTION Help spot hidden scams online. With the built-in Genie AI assistant, you’ll never wonder if a message or email is suspicious again.
- REAL-TIME PROTECTION Advanced security protects against existing and emerging malware threats, including ransomware and viruses, and it won’t slow down your device performance.
- DARK WEB MONITORING Identity thieves can buy or sell your information on websites and forums. We search the dark web and notify you should your information be found.
Before installing an iPhone security app, confirm which features are available on iOS and whether they require a subscription. The fact that an app is available for iOS does not establish that it provides device-wide malware scanning or that every feature is included for free.
How to set up free protection safely
- Check the protection already on your PC. Open Windows Security and visit Virus & threat protection. Confirm Microsoft Defender Antivirus is active if you are not using another antivirus.
- If you install another Windows antivirus, verify the edition. Choose the exact free product only if its current terms meet your needs. Check Windows Security afterward to make sure active protection has not been left disabled. Do not run competing real-time antivirus products together unless their vendors explicitly support that setup.
- Use platform-specific protections on your phone. On Android, install from Google Play and review permissions. On iPhone, keep iOS current and evaluate an app for its documented anti-phishing, web or identity features rather than assuming it can scan other apps.
- Keep the operating system and applications patched. AV-Comparatives notes that fully updated software makes exploits harder to use. Its Windows 11 test environment was fully patched, which made exploit delivery more difficult where third-party application vulnerabilities had already been fixed.
What free antivirus cannot replace
Antivirus is one layer of protection, not a substitute for software updates or careful account and link habits. AV-Comparatives advises users to keep systems and third-party applications patched because doing so can “dramatically decrease the risk posed by exploits.” A strong lab score is evidence about a particular test period, product and platform—not a promise that an infected file, scam or newly discovered vulnerability will always be blocked.
Quick Recap
Best Value
- POWERFUL, LIGHTNING-FAST ANTIVIRUS: Protects your computer from viruses and malware through the cloud; Webroot scans faster, uses fewer system resources and safeguards your devices in real-time by identifying and blocking new threats
- IDENTITY THEFT PROTECTION: Protects your usernames, account numbers and other personal information against keyloggers, spyware and other online threats targeting valuable personal data
- REAL-TIME ANTI-PHISHING: Proactively scans websites, emails and other communications and warns you of potential danger before you click to effectively stop malicious attempts to steal your personal information
- ALWAYS UP TO DATE: Webroot scours 95% of the Internet three times per day including billions of web pages, files and apps to determine what is safe online and enhances the software automatically without time-consuming updates
Rank #4
- THREAT DETECTION – Stay one step ahead. Suspicious links, risky sites, viruses, and scams, caught automatically before they reach you.
- PERSONAL INFO PROTECTION – Keep your personal info safer. Identity monitoring watches for your exposed info and tells you what to do about it.
- SECURE CONNECTIONS – Just a few easy clicks, and we'll automatically protect your info on public Wi‑Fi, every time you connect.
- GUIDED ACTION – Know what matters and what to do next. Clear alerts and simple guidance make it easy to take action.
- MORE THAN ANTIVIRUS – Scam protection, identity monitoring, VPN, web protection, and antivirus work together to protect you, all in one place.
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