Is Windows Defender Safe?

Windows Defender — Nerq Trust Score 65.2/100 (B- grade). Score based on 2 independent trust signals. Last analyzed: 2026-04-02

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. Last analyzed: 2026-04-02 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?

Trust Score Breakdown — Windows Defender has a Nerq Trust Score of 65.2/100 (B-). Measured across 2 independent trust signals (as of 2026-04-02).

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.

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.

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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.

Measured Signals

Windows Defender has a Nerq Trust Score of 65/100 (B-). This score is a composite of automated measurements of security, maintenance, community, and quality signals.

Key Takeaways

Frequently Asked Questions

Is Windows Defender Safe?
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 recomputes Windows Defender's trust score as new data becomes available. Current: 65.2/100 (B-), measured 2026-04-02. API: GET nerq.ai/v1/preflight?target=Windows Defender
Can I use Windows Defender in a regulated environment?
Windows Defender: 65.2/100 (B-). Compliance signals are shown in the breakdown above. Evaluate against your own regulatory requirements.
API: /v1/preflight Trust Badge API Docs

See Also

Disclaimer: Nerq trust scores are automated measurements based on publicly available signals. They are not endorsements, verdicts, or guarantees of suitability. Always evaluate the signals against your own requirements.

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