Windows Defender antivirus review: Is Microsoft's built-in protection enough?
Windows Defender, now known as Microsoft Defender Antivirus and part of Windows Security, is the built-in security solution in Windows 10 and 11, providing protection against malware, ransomware, and real-time threats for free.
In 2025, with the end of support for Windows 10 in October, many users are wondering if this built-in tool is enough to protect their devices without the need for third-party antivirus software.
Based on independent testing and recent reviews, this analysis assesses its effectiveness, strengths, limitations, and whether it is worth supplementing with additional software. Windows 11 Troubleshooting Guide: How to Fix Them
Effectiveness against malware: Test results
Microsoft Defender has improved significantly in recent years, with strong results in independent labs such as AV-Test and AV-Comparatives. In AV-Test's January-February 2025 tests, Defender scored a perfect 6/6 for protection against prevalent malware and zero-day threats, blocking 100% of malicious samples and only 10 false positives. AV-Comparatives reported a 98.6% detection rate in April 2025, with only 10 false positives, placing it among the best in its category. In internal testing in January 2025, Defender blocked 100% of malicious downloads, although it took longer to complete scans (28% CPU usage for more than 10 minutes).
These results position it as a solid option for most users, outperforming some free antivirus programs and competing with premium options like Norton or Bitdefender in basic detection. However, in high-threat scenarios, such as targeted attacks, it may fail to detect some zero-days, where Norton or TotalAV achieve 100% detection with fewer false positives.
ExampleIn a ThreatLocker test in July 2024, Defender blocked most malware, but did not prevent the global CrowdStrike breach, highlighting its reliance on timely updates.
Strengths of Windows Defender
Defender shines in its native integration and core features:
- Real-time protection: Blocks threats instantly, with 100% results in AV-Test tests.
- Offline scanningEffective against rootkits, although less convenient than Norton.
- SmartScreen: Blocks phishing sites and malicious downloads, with 100% effectiveness in AllAboutCookies tests.
- Parental controlsContent filters and time limits, although less intuitive than competitors.
- Windows support: Free, pre-installed, with seamless integration into Windows 11.
| Fortaleza | Effectiveness | Comparison |
|---|---|---|
| Malware | 100% (AV-Test) | Just like Norton |
| Phishing | 100% (AllAboutCookies) | Superior to Chrome Safe Browsing |
| Offline scanning | Cash | Less convenient than Bitdefender |
ExampleDefender blocks 100% of malicious downloads in April 2025 testing, protecting against common threats without slowing down your PC.
Limitations of Windows Defender
Although solid, Defender has weaknesses that make it insufficient for some:
- Lack of VPNIt does not include a free VPN; competitors like Norton offer one. VPN unlimited.
- identity managementLimited dark web monitoring; Norton offers coverage up to $1 million.
- Webcam/mic protection: Absent; competitors such as McAfee include it.
- Slow scanning: Full scans take longer (28% CPU vs. 10 minutes in Norton).
- false positives: 10 in AV-Comparatives tests, more than TotalAV (0).
ExampleDefender allows more threats than McAfee in phishing tests, where McAfee blocks 100%.
Comparison with premium antivirus
In 2025, Defender is "sufficient" for basic users, but premium options like Norton or TotalAV surpass it in coverage.
| Appearance | Defender | Norton | Total AV |
|---|---|---|---|
| Malware | 100% | 100% | 100% |
| Phishing | 100% | 100% | 100% |
| VPN | No | Yes (unlimited) | Yes (premium) |
| Dark Web | Limited Time | $1M coverage | Eventing |
| Scanning | 28% CPU, slow | Quick, 10 min | Fast |
| Price | Free | $ 49.99 / year | $ 39 / year |
Source: AV-Test, AV-Comparatives (January-April 2025).
Defender is "good" for 98.6-100% detection, but Norton and TotalAV offer VPN, identity, and faster scans.
Is that enough for 2025?
For basic users (browsing, email, casual downloads), Defender is sufficient, with 100% detection in testing and free integration. For advanced users (remote work, banking, families), supplement with premium for VPN, identity, and audio/video protection.
ExampleA student uses Defender for browsing; a remote professional adds Norton for VPN.
Tips for maximizing Defender in 2025
- Activate all functions: In Windows security > virus protection, enables “Real-time protection” and “Cloud-based”.
- Scan regularly: Weekly scan schedule.
- Use SmartScreen: Activate to block risky downloads.
- Update WindowsMonthly patches (KB5041585, September 2025) fix vulnerabilities.
- Add if necessaryAdd a VPN (free ProtonVPN) or password manager (Bitwarden).
ExampleActivate SmartScreen to block phishing while browsing.
Conclusion
Windows Defender It's a free and effective solution in 2025, with 100% malware detection in AV-Test and AV-Comparatives tests, outperforming some premium options in basics. However, it lacks VPN, identity monitoring, and webcam protection, where Norton and TotalAV excel. For most users, it's sufficient; for high-risk situations, combine it with a premium solution. Keep it updated and maintain safe practices for optimal protection.
FAQs
- Is defending enough by 2025?
Yes for basic users; add premium for extras like VPN. - What score did you get on AV-Test?
6/6 in protection, performance and usability (January 2025). - Does Defender have a VPN?
No; use Microsoft 365 VPN (limited or premium) like Norton. - How to complement it?
Add Norton or TotalAV for identity and VPN.
