Head-to-head · Antivirus Software
Microsoft Defender Antivirus vs Avira Free Security
Microsoft Defender Antivirus leads on 0 checks, Avira Free Security on 1, and 3 are even. Who comes out ahead on the 4 yes/no, price and count checks where we have data for both products. The editor score weighs everything else too.
Our verdict
- Highest scoreMicrosoft Defender Antivirus · 7.9/10
- Free planboth
- Most featuresAvira Free Security · 2 of 3
Microsoft Defender Antivirus scores higher on our rubric for antivirus software: 7.9 against 6.6 out of 10; our editors rank them #14 and #28.
On protection scope, Avira Free Security gives you Internet security where Microsoft Defender Antivirus offers Antivirus. Avira Free Security offers password manager; Microsoft Defender Antivirus doesn't.
Microsoft Defender Antivirus is the better fit for free Windows antivirus protection. Avira Free Security is the better fit for free, multi-platform personal antivirus.
- Microsoft Defender Antivirus fits best
Free Windows antivirus protection
- Avira Free Security fits best
Free, multi-platform personal antivirus
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Side by side
| Feature | Microsoft Defender Antivirus 7.9/10 Visit ↗ | Avira Free Security 6.6/10 Visit ↗ |
|---|---|---|
| At a glance | ||
| Editor score | 7.9 | 6.6 |
| Ranking | #14 in Antivirus Software | #28 in Antivirus Software |
| Best for | Free Windows antivirus protection | Free, multi-platform personal antivirus |
| Pricing model | Free plan + paid | Free plan + paid |
| Starting price | — | — |
| Free plan | ✓ | ✓ |
| Free trial | — | — |
| Deployment | Desktop | Desktop, Mobile |
| Platforms | Windows | Windows, macOS, Android, iOS |
| Features Microsoft Defender Antivirus 1/3 · Avira Free Security 2/3 | ||
| Ransomware protection | ✓ | ✓ |
| Parental controls | — | — |
| Password manager | — | ✓ (best) |
| Specs | ||
| Protection scope | Antivirus | Internet security |
| Device limit | Not checked yet | Not checked yet |
| Supported platforms | Windows 10, Windows 11 | Windows, macOS, Android, iOS |
| Our review | ||
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| Our verdict | Microsoft Defender Antivirus is a free, real-time antivirus product built into Windows. It is designed for personal Windows 10 and Windows 11 devices, protecting against viruses, malware, spyware, and other threats without a separately… Read the review → |
Avira Free Security is a free consumer security package for protecting devices against malware and ransomware. Its coverage spans Windows, macOS, Android, and iOS, with features that include full virus scanning, real-time antivirus… Read the review → |
Strengths and trade-offs
Microsoft Defender Antivirus — where it wins
- Always-on protection with quick, full, custom, and offline scans
- Controlled folder access adds ransomware-focused protection
- SmartScreen and Windows Firewall integration extend Windows protection
Where it doesn't
- Works on Windows 10 and Windows 11 devices only
- Focused on antivirus rather than a broader standalone security suite
- Designed for Windows devices instead of multi-platform coverage
Avira Free Security — where it wins
- Free plan covers Windows, macOS, Android, and iOS
- Combines real-time, ransomware, browser, and virus protection
- Adds VPN, password management, cleanup, and update tools
Where it doesn't
- Feature availability varies by operating system
- Parental controls are not included
- The free package is aimed at consumers rather than broader security needs
- Microsoft Defender Antivirus7.9/10 · Free plan
A free Windows antivirus with always-on protection and ransomware controls.
Visit MicrosoftFull verdict → - Avira Free Security6.6/10 · Free plan
A broad free antivirus package for personal protection across four major platforms.
Visit AviraFull verdict →
All antivirus software comparisons → · Full ranking →
Reviewed by iTechGuides Editors · Editorial team · Updated Oct 2026
Last updated · How we research and update