Strengthen your PC’s security with Avast Free Antivirus for Windows 11
Get powerful real-time protection against viruses and other malware. Strengthen your Windows 11 security and privacy with Avast Free Antivirus — it's trusted by over 400 million people worldwide, download it free now.
Award-winning virus and malware protection
Home Wi-Fi network security
Easy to install, Effortless to use
30+ years of protecting our users
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 essential free antivirus protection
Browse, shop, and bank securely
Protect your personal files
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.
Easy to install, effortless to use
It only takes moments to install Avast Free Antivirus and the software is simple 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.
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 virus attacks on Windows 11 PCs over recent months.
The United States’ Windows 11 PCs are the third most attacked in the world.
Number of attacks prevented against Windows 11 PCs in recent months:
Here’s what our users say:
Already have Avast? We’ve got you covered
If you’re upgrading from older versions of Windows, such as XP, Vista, 7, 8,8.1, or 10, you can keep your new Windows 11 PC virus-free. Make sure you’re running the latest version of Avast before you upgrade. Once you’ve transitioned to Windows 11, you can browse the internet with complete confidence, knowing that both your online security and computer are in safe hands.
How to install
2. Open the file
3. Install the file
All devices require an internet connection for automatic security and program updates.
Is Avast Free Antivirus compatible with Windows 11?
Does Windows 11 need an antivirus?
This antivirus can detect any security weaknesses in real time and blocks viruses, spyware, Trojans, and other types of malware — all completely free.
Is it safe to upgrade to Windows 11?
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.
Does Windows 11 have better security than older versions?
You can combine the new security features with antivirus software to make your PC even more secure. Avast 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.
Will Avast Free Antivirus affect the performance of your Windows 11 PC?
You can boost the performance of your PC further by using our cleanup tool to clean up, speed up, and tune up your device.
Does Windows 11 come with antivirus software?
Is Windows 11 safe?
Is the Windows 11 firewall sufficient?
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