Protect your Windows 8.1 PC with Avast Free Antivirus
Your Windows 8.1 PC deserves an antivirus trusted by hundreds of millions of users worldwide.
Get your Windows 8.1 PC running smoothly
We’re more than just free antivirus. Avast also protects your Windows 8.1 PC’s performance, using cloud-based processing to secure you without slowing you down. In addition, you can optimize Windows 8.1 with Avast Cleanup, which will adjust settings, clear junk data, and clean out your registry to get your Windows 8.1 PC running as good as new.
Essential antivirus protection for Windows 8.1
Avast Free Antivirus has been tested on Windows 8.1 by AV Comparatives, who found we offer 100% protection against zero-day malware attacks. That, combined with our growing suite of security features such as Avast SecureLine and Avast Passwords, will ensure that no threat will put you or your PC at risk.
Microsoft-approved security for Windows 8.1
Avast is one of Microsoft's official consumer security software providers – ensuring our place as one of the most beloved, trusted antiviruses on the net, used by hundreds of millions of users around the globe.
The people have spoken
Great protection of my laptop with Windows 8.1. Thanks!
Best antivirus on the planet!
Very good antivirus software. I like it doesn't slow down my computer and it's free.
FAQs
Every PC needs protection and Windows 8.1 PCs are no exception. Windows 8.1 does have built-in security software, however, it is widely accepted that this built-in security is not enough. Therefore for better online security, you need a third-party antivirus to keep you safe from viruses, ransomware, and other malware.
Windows 8.1 does have Windows Defender built-in, however, it only offers basic protection to Windows 8.1 PCs. Therefore, for true online security, it would benefit you and your device to invest in third-party antivirus software that can make up for the limitations of Windows Defender.
Yes. Windows Defender is free, as it comes built-into Windows 8.1. However, if you’re looking for more comprehensive security software, Avast offers a free antivirus for Windows 8.1. The free version of Avast Antivirus for Windows 8.1 provides powerful and comprehensive protection that should more than suffice for your needs. If you would like more security, however, you can also download a 30-day free trial of Avast Premium.
Avast Free Antivirus for Windows is one of the best Windows antiviruses by far due to our powerful security and additional features. We use six layers of security to ensure you have protection from 0-day threats. Additionally, our automatic spyware removal tool can keep your data private, and we make removing viruses already on your Windows 8.1 PC easy. Best of all, we’re absolutely free, so you can download and install our protection without paying anything.
Visit our Support Center for more FAQs
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