Strengthen your PC’s security with our free antivirus for Windows 11

Get powerful, real-time antivirus protection for your Windows PC or laptop and strengthen your privacy. Avast One with Free Antivirus is trusted by millions of users worldwide, download it free now.

Also available for Mac, Android, and iOS

AV-Comparatives
January 2026

Top–Rated Product 2025

AV-Test
December 2025

Top Product

AV-Comparatives
January 2026

Top–Rated Product 2025

AV-Test
December 2025

Top Product

Millions of people choose Avast to get:

AI-powered anti-scam guidance

Defense against hidden scams

Safer browsing and emailing

An app that’s easy to install and use

Windows 11 virus protection that comes with extra features

In today’s digital world, sometimes you need more than antivirus to give you the protection you need, so we’ve included some advanced features alongside our award-winning free antivirus, so you’re covered from all angles.

Get crucial, free virus protection for Windows 11
Strengthen your Windows 11 PC security and protect your entire home Wi-Fi network, plus get advanced tools like anti-malware security, Wi-Fi security scans, and more, all completely free.
Browse, shop, and bank securely
Protect your financial info while you browse, shop, and bank online. Scan websites to make sure they’re legitimate, and avoid fake websites trying to steal your information.
Protect your personal files
Keep sensitive information safe. Protect your personal photos, files, and documents and don’t let them become hostage to ransomware.
Get crucial, free virus protection for Windows 11
Strengthen your Windows 11 PC security and protect your entire home Wi-Fi network, plus get advanced tools like anti-malware security, Wi-Fi security scans, and more, all completely free.
Browse, shop, and bank securely
Protect your financial info while you browse, shop, and bank online. Scan websites to make sure they’re legitimate, and avoid fake websites trying to steal your information.
Protect your personal files
Keep sensitive information safe. Protect your personal photos, files, and documents and don’t let them become hostage to ransomware.

You can rely on Avast to protect you

Here’s why Avast is one of the most trusted, reliable, and experienced cybersecurity experts in the world.

Award-winning protection
We’re proud to offer our users world-class protection against cyberthreats, supported by the many awards our antivirus has earned.
Millions of users worldwide
Our vast global user base means we have the largest threat detection network in the industry, so we catch new threats fast.
30+ years of experience
When it comes to creating an antivirus that protects you from all angles, we know exactly what it takes.

Easy to install, effortless to use

Our free antivirus software for Windows 11 installs fast, and it’s easy to use. Clear interfaces and settings allow you to set and automate your security, so it’s always running quietly in the background, protecting you in real time, 24/7. And it’s always free, so give it a try now.

100% free protection

Get award-winning antivirus and protect your Windows 11 PC from viruses and other malware, for free, forever. Plus, get extra features like email shields, hack alerts, Wi-Fi security scanner, and more, all included for free.

Avast Free Antivirus never sleeps

We’re proud to protect millions of Windows PCs. But don’t just take our word for it; see the graph below which shows that Avast has prevented 2 317 553 210 virus attacks on Windows 11 PCs over recent months.

Number of attacks prevented against Windows 11 PCs in recent months:

Avast Free Antivirus never sleeps

We’re proud to protect millions of Windows PCs. But don’t just take our word for it — see the graph below which shows that Avast has prevented 2 317 553 210 virus attacks on Windows 11 PCs over recent months.

Number of attacks prevented against Windows 11 PCs in recent months:

We’re award-winning by nature, not just by name

We can help protect you against advanced online threats, backed by one of the world’s largest consumer Cyber Safety networks. And we’ve been proud winners of different awards over the years. Check out some of our more recent ones below. The award-winning protection from Avast Free Antivirus is also available in the Avast One app.

2025

“95% phishing-page detection rate, no false alarms”

AV-Comparatives
Anti-Phishing Comparative Test

 

2025

“100% real-world threat samples detected and blocked”

AV Test
Home User Protection Test


 

2025

“Total Accuracy Rating: 100%, False Positives: 0%”

SE Labs 
Security Evaluation Test: Home Anti-Malware

2025

“95% phishing-page detection rate, no false alarms”

AV-Comparatives
Anti-Phishing Comparative Test

2025

“100% real-world threat samples detected and blocked”

AV Test
Home User Protection Test

2025

“Total Accuracy Rating: 100%, False Positives: 0%”

SE Labs 
Security Evaluation Test: Home Anti-Malware

Resolve security issues quickly and more

Avast’s antivirus scans for security and performance issues and helps you to fix them instantly. It also protects you in real time by analyzing unknown files long before they reach your Windows 11 PC. And it’s free, so give it a try.

Also available for Mac, Android, and iOS

Already have Avast? We’ve got you covered

If you’re planning on upgrading from older versions of Windows, such as 7, 88.1, or 10, we’re ready to keep your Windows 11 PC virus-free. Just make sure you’re running the latest version of Avast before you upgrade your machine, and when you finish the transition to Windows 11, you’ll find us there, right where you left us, ready to protect your PC and everything you hold dear in it. 

You may still be wondering...

FAQs

It’s 100% compatible. Microsoft supports the Avast One app with Free Antivirus on all Windows 11 devices. You can easily download and run the installer in minutes and be protected right away.

Windows 11 has a built-in security center where you can enable basic security tools. Even though Microsoft Windows comes with Windows Defender built-in, it’s not enough protection. Luckily, Microsoft makes it easy to install antivirus software that specifically provides advanced protection and security, such as the Avast One app with Free Antivirus.

This antivirus can detect any security weaknesses in real time and blocks viruses, spyware, Trojans, and other types of malware, all completely free.

Yes, it’s safe and free to upgrade to Windows 11, just as Windows 10 was a free upgrade for PCs running Windows 7 and Windows 8. As long as your PC meets Microsoft's minimum system requirements, you’ll be able to access Windows 11 minimal security features.

To make your PC safer, we recommend using an effective free antivirus to add an extra layer of online security and a secure VPN to encrypt your connection for greater privacy.

Windows 11 is a more secure operating system than older versions of Windows. To get the most secure version of Windows 11, you can find new security features in the Windows Operating System.

You can combine the new security features with antivirus software to make your PC even more secure. The Avast One app with Free Antivirus can make sure malicious websites and vulnerable Wi-Fi networks don’t jeopardize your online safety. It also includes advanced features like web and email shields, Wi-Fi security scanners, and more.

Not at all. The Avast One app provides the lowest impact on PC performance. Whether you use your PC for gaming or for work, Avast gives you reliable protection without affecting the performance of your PC at any time.

You can boost the performance of your PC further by using our cleanup tool to clean up, speed up, and tune up your device.

Yes, Windows comes with its own built-in protection called Windows Defender, which offers basic protection but won’t fully protect you against all threats. It’s recommended that you install an individual antivirus, like the Avast One app with Free Antivirus, to ensure that there are no gaps in your security and that you’re always completely protected, even from advanced threats.

Yes, Windows 11 is a very safe product. It was created by Microsoft and is used by people all over the world.

Windows firewall will provide some protection but we recommend using an advanced firewall like the one included in the Avast One app. It offers comprehensive protection against unauthorized communications and intrusions to your system.

Visit our Support Center for more FAQs

Get security tips and advice straight from the experts