Microsoft Defender, the built-in antivirus solution for Windows 11, has been a reliable option for many users. However, recent evaluations by AV-Test in June 2026 reveal that it still lags behind two free competitors: Avast Free Antivirus and AVG AntiVirus Free, both of which achieved a perfect score of 18 out of 18. In contrast, Defender’s Consumer engine (version 4.18) scored 17.5, while Avira Internet Security followed with a score of 16.5. This raises an important question for users: is Defender sufficient, or should they consider third-party options?
What “best free antivirus” actually means in 2026
The term “best free antivirus” is often used without clarity. In 2026, independent testing labs like AV-Test and AV-Comparatives evaluate consumer security products based on three key criteria: protection, performance, and usability. A product that excels in malware detection but frequently misidentifies legitimate software as threats is not ideal for everyday use.
In the latest evaluations, 16 consumer antivirus products were tested, with eight achieving the maximum score. Notably, Avast Free Antivirus and AVG AntiVirus Free are true free offerings, unlike many others that are merely trial versions of paid suites. This guide focuses on products with ongoing free tiers: Microsoft Defender, Avast Free Antivirus, AVG AntiVirus Free, Bitdefender’s free tier, and Avira Free Security.
How AV-Test and AV-Comparatives actually score these products
Understanding the scoring system is crucial for making informed decisions. AV-Test employs continuous evaluation cycles, exposing products to real-world malware samples and zero-day threats. Each category—protection, performance, and usability—is scored out of 6.0, leading to a maximum total of 18.0. A product must meet minimum thresholds across all categories to earn certification.
AV-Comparatives uses a different methodology, focusing on live malicious URLs, which rewards products with strong web-filtering capabilities. This distinction is why this guide emphasizes AV-Test’s results for Windows 11 home users, ensuring clarity and relevance in the comparisons.
Prerequisites: what you need before you start
- Operating system: Windows 11, version 24H2 or later, 64-bit.
- Administrator account: Required for installing or removing security software.
- Free disk space: A few hundred megabytes for Defender-only setups, up to roughly 2GB for third-party installations.
- Stable internet connection: Necessary for downloading installers and updates.
- PowerShell 5.1 or later: Included in Windows 11 for auditing and verification.
- Target software versions: Ensure you have the latest versions of the antivirus products you intend to install.
- Only one real-time antivirus engine at a time: Running multiple engines can cause conflicts.
Step 1 – Audit what’s already protecting your PC
Before installing a new antivirus, it’s essential to know what is currently active on your system. Most Windows 11 PCs come with Microsoft Defender enabled by default, but leftover trial software can interfere with its operation. Use PowerShell to check the status of Defender and any other antivirus products:
Get-MpComputerStatus | Select-Object AMServiceEnabled, AntispywareEnabled, AntivirusEnabled, RealTimeProtectionEnabled, AntivirusSignatureVersion, AntivirusSignatureLastUpdatedThis command will help you determine if Defender is actively protecting your system or if another product is interfering.
Step 2 – Compare the 2026 AV-Test scores for free antivirus
With a clear understanding of your current protection, compare the latest AV-Test results for free antivirus products:
| Product | Version tested | Protection | Performance | Usability | Total score | Cost |
|---|---|---|---|---|---|---|
| Avast Free Antivirus | 26.4 / 26.5 | 6.0 / 6.0 | 6.0 / 6.0 | 6.0 / 6.0 | 18 / 18 | Free |
| AVG AntiVirus Free | 26.4 / 26.5 | 6.0 / 6.0 | 6.0 / 6.0 | 6.0 / 6.0 | 18 / 18 | Free |
| Microsoft Defender (Windows Security) | 4.18 | Certified | Certified | Certified | 17.5 / 18 | Free (built-in) |
| Bitdefender (shared engine, Total Security 27.0) | 27.0 | Certified | Certified | Certified | Top-tier, certified | Free tier available |
| Avira Internet Security | Current release | Certified | Certified | Certified | 16.5 / 18 | Free tier available |
The takeaway is clear: for those seeking the highest lab-tested scores for free antivirus, Avast and AVG stand out. Microsoft Defender remains a solid choice, especially for users who prefer a no-fuss, built-in solution.
Step 3 – Decide: Defender alone, or a third-party layer
At this juncture, users must decide whether to stick with Defender or add a third-party antivirus. If you prefer simplicity and minimal setup, Defender is adequate for low-risk users. However, for those who require enhanced protection and additional features, installing Avast or AVG may be beneficial.
Free antivirus vs paid: what you actually give up
Understanding the differences between free and paid antivirus options is crucial. While the core malware detection capabilities are similar, paid tiers often offer additional features such as advanced firewalls, VPNs, and identity theft monitoring. For single-device users, the free options provide robust protection without the need for a paid upgrade.
Step 4 – Remove conflicting antivirus software first
If you discover any previous antivirus software, ensure it is fully uninstalled before proceeding with a new installation. Use Windows’ built-in uninstaller to remove any remnants of old software, as leftover components can hinder the performance of your new antivirus.
Step 5 – Download and verify your installer
Always download antivirus software from the official vendor’s website to avoid scams. After downloading, verify the digital signature to ensure the file is legitimate before running the installer.
Step 6 – Install Avast, AVG, Bitdefender or Avira Free
Run the installer as an Administrator and follow the prompts. Decline any bundled extras unless you specifically want them, as they can add unnecessary background processes.
Step 7 – Configure real-time protection and exclusions
After installation, configure real-time protection and set exclusions for trusted folders to optimize performance. This step is crucial for ensuring that your antivirus runs smoothly without unnecessary interruptions.
Step 8 – Schedule automatic scans
Set up a weekly scan to catch any threats that may slip through. This proactive measure helps maintain your system’s security over time.
Step 9 – Lock down ransomware protection and the firewall
Ensure that your firewall is active and properly configured. If using a third-party antivirus, confirm that it is managing the firewall effectively without conflicts.
Step 10 – Add browser and phishing protection, then test with EICAR
Enable browser protection features and conduct an EICAR test to verify that your antivirus is functioning correctly. This step is essential for confirming that real-time protection is operational.
Step 11 – Automate updates and verify protection status
Regularly check that your antivirus is updating automatically. Keeping your software current is vital for maintaining protection against emerging threats.
Common pitfalls when setting up free antivirus
- Running two real-time engines: This can lead to performance issues and conflicts.
- Accepting bundled extras: Avoid unnecessary tools that don’t enhance protection.
- Downloading from unofficial sources: Always use the vendor’s website to prevent scams.
- Assuming dashboard status is accurate: Conduct tests like the EICAR to confirm functionality.
- Ignoring update status: Regularly check for updates to ensure ongoing protection.
Troubleshooting common free antivirus problems
- “Real-time protection is off”: Check for leftover drivers from previous installations.
- EICAR test file not detected: Ensure the antivirus is updated and not excluding the download folder.
- PC slower after install: Reschedule scans to idle times to improve performance.
Which free antivirus fits your situation
| Situation | Recommended pick | Why |
|---|---|---|
| Low-risk everyday user | Microsoft Defender | No setup required, solid protection. |
| Wants highest lab-tested score | Avast or AVG | Both achieved 18/18 in testing. |
| Higher risk profile | Avast or AVG with ransomware shield | Additional protection features. |
Advanced tips: building a layered free security stack
- On-demand second-opinion scanner: Use tools that run scheduled scans without real-time protection.
- DNS-level filtering: Implement a filtering DNS resolver for added security.
- Full-disk encryption: Pair antivirus with encryption for physical theft protection.
Complete working project: a one-page free antivirus checklist
Get-CimInstance -Namespace "rootSecurityCenter2" -ClassName AntiVirusProduct | Select-Object displayName, productStateFrequently asked questions
Is free antivirus actually good enough in 2026?
Yes, for most home users, the free options available today provide robust protection.
Do I need to disable Microsoft Defender if I install Avast or AVG?
No, Windows will automatically manage this transition.
Which free antivirus scored highest in the latest AV-Test results?
Avast Free Antivirus and AVG AntiVirus Free both achieved a score of 18/18.
Is it safe to run two antivirus programs at the same time?
No, this can lead to conflicts and performance issues.
What is the EICAR test file?
EICAR is a harmless test file used to verify antivirus functionality.
Why does my free antivirus keep asking me to upgrade?
This is standard behavior for freemium models, and does not indicate a loss of protection.
How often should free antivirus signatures update?
Typically, updates occur multiple times per day; ensure this is functioning correctly.
Should I still pay for antivirus if the free version scores well?
If you only need basic malware protection, the free versions are sufficient. Paid tiers offer additional features rather than improved detection.
![Best Free Antivirus: 11 Steps, 18/18 Score [2026]](https://newapp.site/wp-content/uploads/2026/09/best-free-antivirus-11-steps-18-18-score-2026.webp)