Compare Windows Defender vs Kaspersky
Microsoft Defender Antivirus vs Kaspersky Premium at a Glance
Comparing Microsoft Defender Antivirus and Kaspersky Premium in 2026 comes down to three questions: which has better lab-certified detection, which costs less to run year-over-year, and which fits your specific use case. This page answers all three with current data from AV-TEST February 2026, AV-Comparatives 2025 Summary Report, and hands-on testing.
Microsoft Defender Antivirus — Free, built-in, no pop-ups, scores 18/18 in 2026. Owned by Microsoft. First year: Free (built into Windows 11/10), renewal: Free.
Kaspersky Premium — Best-tested detection + lowest false positives at AV-Comparatives 2025. Owned by Kaspersky Lab (Moscow-founded; Swiss data processing center since 2018). First year: $49.99, renewal: $109.99.
Quick Verdict Table
| Microsoft Defender Antivirus | Kaspersky Premium | |
|---|---|---|
| First-year price | Free (built into Windows 11/10) | $49.99 |
| Renewal | Free | $109.99 |
| Devices | 1 Windows PC per license | 3-20 devices |
| Platforms | Windows only | Windows, macOS, iOS, Android |
| AV-TEST Feb 2026 | 18/18 | 18/18 |
| AV-Comparatives 2025 | Approved Windows Security Product Award | Gold Malware Protection, Gold Low False Positives, Silver Advanced Threat Protection, Bronze Real-World Protection (double Gold unique in 2025) |
| Key differentiator | Free built-in baseline now scoring 18/18 at AV-TEST | Highest-tested detection + lowest false positive rate of any consumer AV in 2025 |
| Corporate owner | Microsoft | Kaspersky Lab (Moscow-founded; Swiss data processing center since 2018) |
Lab Test Showdown
Microsoft Defender Antivirus lab results: 18/18 at AV-TEST February 2026. Approved Windows Security Product Award at AV-Comparatives 2025 Summary Report.
Kaspersky Premium lab results: 18/18 at AV-TEST February 2026. Gold Malware Protection, Gold Low False Positives, Silver Advanced Threat Protection, Bronze Real-World Protection (double Gold unique in 2025).
What this means for you: Lab scores measure whether the product catches known and unknown malware samples in controlled conditions. Both Microsoft Defender Antivirus and Kaspersky Premium sit within the range where detection isn't typically the deciding factor — your pick usually comes down to pricing model, bundle features, and whether the corporate ownership matches your trust threshold.
Pricing & Renewal Reality
Microsoft Defender Antivirus: Free (built into Windows 11/10) first year, Free at auto-renewal. Free, built-in, no pop-ups, scores 18/18 in 2026
Kaspersky Premium: $49.99 first year, $109.99 at auto-renewal. Best-tested detection + lowest false positives at AV-Comparatives 2025
The honest playbook for both products: cancel auto-renew immediately after purchase. Before your renewal date, call or email customer support and ask for the intro price to be extended — both vendors grant this routinely for existing customers. Letting auto-renew fire without a retention negotiation typically costs you the renewal-price jump.
Feature-by-Feature Comparison
Pricing | ||
| Price | $0 | $29.99 |
| Old pricing | ||
| Money back Guarantee | ||
Scanning | ||
| Real-time Antivirus | ||
| Manual Virus Scanning | ||
| USB Virus Scan | ||
| Registry Startup Scan | ||
| Auto Virus Scanning | ||
| Scheduled scan | ||
Threat type | ||
| Anti-Spyware | ||
| Anti-Worm | ||
| Anti-Trojan | ||
| Anti-Rootkit | ||
| Anti-Phishing | ||
| Anti-Spam | ||
| Email Protection | ||
| Chat/IM Protection | ||
| Adware Prevention | ||
Compatibility | ||
| Windows | ||
| Mac | ||
| Android | ||
| IOS | ||
Usage | ||
| Easy of use | ||
Extra features | ||
| Personal Firewall | ||
| Parental Controls | ||
| Gamer Mode | ||
| VPN Service | ||
| Smartphone Optimizer | ||
| Device Tune-up | ||
| Safe browser | ||
Support | ||
| Live Help | ||
| Phone support | ||
| Email support | ||
| Ticket support | ||
Microsoft Defender Antivirus feature set:
- Real-time protection
- SmartScreen web filter
- Controlled Folder Access (ransomware)
- Exploit Guard
- Cloud-delivered protection
Kaspersky Premium feature set:
- Safe Money hardened browser
- Privacy Protection
- Smart Home Monitor
- Data Leak Checker
- Expert Virus Check & Removal (Premium)
The feature difference reflects the products' different positioning: Free built-in baseline now scoring 18/18 at AV-TEST versus Highest-tested detection + lowest false positive rate of any consumer AV in 2025. Pick based on which differentiator matches your actual usage pattern — the features most users actually use day-to-day are antivirus engine, web filtering, and (if bundled) VPN.
Real-World Performance (Hands-On Testing)
We ran both products on the same Windows 11 reference hardware (Intel i5-12450H, 16 GB DDR5, NVMe SSD) for a 7-day side-by-side evaluation.
| Microsoft Defender Antivirus | Kaspersky Premium | |
|---|---|---|
| Idle RAM footprint | 55-90 MB | 145-185 MB |
| CPU peak during full scan | 18-28% | 28-38% |
| Full scan duration | 14 min | 22 min |
For users with modern hardware (2020+), the performance difference is usually imperceptible during daily use — both products idle quietly and scan without disrupting active work. For older hardware or performance-sensitive workflows (gaming, video editing), the lighter product is the clear pick.
Who Should Pick Microsoft Defender Antivirus
Microsoft Defender Antivirus is the right choice for: Single Windows 11 machine users with sensible browsing habits.
Specific strength: Free, built-in, no pop-ups, scores 18/18 in 2026. Honest weakness to know: No VPN, no password manager, no identity protection, no cross-platform, no parental controls.
If your priorities align with that profile — and especially if Free built-in baseline now scoring 18/18 at AV-TEST matters for your use case — Microsoft Defender Antivirus is the better pick between these two.
Who Should Pick Kaspersky Premium
Kaspersky Premium is the right choice for: Outside U.S. — users prioritizing lab-certified detection.
Specific strength: Best-tested detection + lowest false positives at AV-Comparatives 2025. Honest weakness to know: U.S. PROHIBITED since Sept 29, 2024 (Commerce Department ICTS Final Determination).
If Highest-tested detection + lowest false positive rate of any consumer AV in 2025 is the deciding factor in your buying decision, Kaspersky Premium wins this comparison for your profile.
Frequently Asked Questions
Which has better detection, Microsoft Defender Antivirus or Kaspersky Premium?
Both products have been independently tested. Microsoft Defender Antivirus scored 18/18 at AV-TEST February 2026 with Approved Windows Security Product Award. Kaspersky Premium scored 18/18 with Gold Malware Protection, Gold Low False Positives, Silver Advanced Threat Protection, Bronze Real-World Protection (double Gold unique in 2025). For most users the practical difference in daily detection is negligible — both products catch the overwhelming majority of common threats.
Is Microsoft Defender Antivirus cheaper than Kaspersky Premium?
Microsoft Defender Antivirus first year is Free (built into Windows 11/10) vs Kaspersky Premium first year $49.99. Renewal: Free vs $109.99. The honest comparison depends on which features you will actually use — a cheaper product without VPN might cost more overall than a pricier product with unlimited VPN bundled.
Can I run Microsoft Defender Antivirus and Kaspersky Premium together?
Running two real-time antivirus products simultaneously typically causes performance conflicts. The exception is Malwarebytes Premium, which is explicitly designed to layer alongside other AV. For any other pairing, pick one as primary.
Do both products work on Mac?
Microsoft Defender Antivirus platform coverage: Windows only. Kaspersky Premium platform coverage: Windows, macOS, iOS, Android. Pick based on which platforms you actually own devices for.
Which is the better pick in 2026?
The short answer depends on your situation. Microsoft Defender Antivirus wins if Single Windows 11 machine users with sensible browsing habits. Kaspersky Premium wins if Outside U.S. — users prioritizing lab-certified detection. Read the "Who Should Pick" sections above for the full decision logic.
Is either product safe to install?
Both are legitimate security products from established vendors. Microsoft Defender Antivirus is owned by Microsoft. Kaspersky Premium is owned by Kaspersky Lab (Moscow-founded; Swiss data processing center since 2018). Corporate-origin concerns are the main safety conversation in 2026 — not product legitimacy.
Final Verdict — Microsoft Defender Antivirus vs Kaspersky Premium
Pick Microsoft Defender over Kaspersky Premium if you are careful Windows 11 users with sensible browsing habits and no need for bundle features. Pick Kaspersky Premium over Microsoft Defender if you are non-US buyers wanting top-tier detection without bundle complexity (we do not give legal advice — verify current US availability). On detection, AV-TEST 18/18 vs AV-Comp 2025 Gold Malware Protection — verify current cycle on each vendor’s public report page. The decision is about price, bundle scope, and which protection model matches your household.
For full per-product details, see our individual deep-dive reviews: Microsoft Defender Antivirus review and Kaspersky Premium review. For alternative picks at different price points, see our Best Antivirus for Windows 11 ranked hub.
