Is Windows Defender Safe?

Windows Defender — Nerq Trust Score 65.2/100 (B- grade). Based on analysis of 2 trust dimensions, it is generally safe but has some concerns. Last updated: 2026-07-22.

Use Windows Defender with some caution. Windows Defender is a antivirus software (now comparable to paid solutions) with a Nerq Trust Score of 65.2/100 (B-), based on 3 independent data dimensions. Below the recommended threshold of 70. Security: 90/100. Popularity: 100/100. Data sourced from multiple public sources including package registries, GitHub, NVD, OSV.dev, and OpenSSF Scorecard. Last updated: 2026-04-02. Machine-readable data (JSON).

Is Windows Defender safe?

CAUTION — Windows Defender has a Nerq Trust Score of 65.2/100 (B-). It has moderate trust signals but shows some areas of concern that warrant attention. Suitable for development use — review security and maintenance signals before production deployment.

Security Analysis → Windows Defender Privacy Report →

What is Windows Defender's trust score?

Windows Defender has a Nerq Trust Score of 65.2/100, earning a B- grade. This score is based on 2 independently measured dimensions including security, maintenance, and community adoption.

Security
90
Popularity
100

What are the key security findings for Windows Defender?

Windows Defender's strongest signal is popularity at 100/100. No known vulnerabilities have been detected. It has not yet reached the Nerq Verified threshold of 70+.

Security score: 90/100 (strong)
Popularity: 100/100 — community adoption

What is Windows Defender and who maintains it?

AuthorUnknown
CategoryAntivirus
SourceN/A

Antivirus Assessment

Independent Lab Results (AV-TEST)

Windows Defender scored 6.0/6 on protection and 5.5/6 on performance in AV-TEST independent testing. Perfect protection score. Slightly higher system impact than top performers.

Security Track Record

Windows Defender has no known major security incidents or privacy scandals.

Build Your Security Stack

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Windows Defender Across Platforms

Same developer/company in other registries:

Windows Defender
48/100 · chrome

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Safety Guide: Windows Defender

What is Windows Defender?

Windows Defender is a antivirus software — Microsoft Defender (formerly Windows Defender) is the built-in antivirus for Windows 10 and 11. Free, no installation required, auto-updates via Windows Update. AV-TEST score: 6/6 protection, 5.5/6 pe.

How to Verify Safety

Check AV-TEST lab results. Review incident history and privacy policy.

You can also check the trust score via API: GET /v1/preflight?target=Windows Defender

Key Safety Concerns for antivirus software

When evaluating any antivirus software, watch for: detection rate, system impact, privacy practices, jurisdiction.

Trust Assessment

Windows Defender has a Nerq Trust Score of 65/100 (B-) and has not yet reached Nerq trust threshold (70+). This score is based on automated analysis of security, maintenance, community, and quality signals.

Key Takeaways

Frequently Asked Questions

Is Windows Defender Safe?
Use with some caution. Windows Defender with a Nerq Trust Score of 65.2/100 (B-). Strongest signal: popularity (100/100). Score based on Security (90/100), Popularity (100/100).
What is Windows Defender's trust score?
Windows Defender: 65.2/100 (B-). Score based on Security (90/100), Popularity (100/100). Scores update as new data becomes available. API: GET nerq.ai/v1/preflight?target=Windows Defender
What are safer alternatives to Windows Defender?
In the Antivirus category, more software tools are being analyzed — check back soon. Windows Defender scores 65.2/100.
How often is Windows Defender's safety score updated?
Nerq continuously monitors Windows Defender and updates its trust score as new data becomes available. Current: 65.2/100 (B-), last verified 2026-07-22. API: GET nerq.ai/v1/preflight?target=Windows Defender
Can I use Windows Defender in a regulated environment?
Windows Defender has not reached the Nerq Verified threshold of 70. Additional due diligence is recommended.
API: /v1/preflight Trust Badge API Docs

See Also

Disclaimer: Nerq trust scores are automated assessments based on publicly available signals. They are not endorsements or guarantees. Always conduct your own due diligence.

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