Best Free Antivirus in 2021

Our breakdown of the options for the best free antivirus tools in 2020

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It’s more important than ever to protect the security of your computer system. As different types of malware and cyberattacks become more sophisticated, you need to use antivirus software that will reliably stay updated to protect against emerging threats.

There are paid options for antivirus software, but before opening your wallet, it’s worth considering one of the many free options available. For the typical user, simply using one of the free antivirus tools available will provide you with perfectly adequate protection.

Just taking the small steps of installing and configuring these antivirus tools will offer you increased protection, and it’s worth doing as soon as possible, rather than waiting until your system has been compromised before thinking about a solution.

Each of these free antivirus tools will help keep you protected, but read on for our breakdown of the advantages and unique features of each option.

Windows Security

(Also known as Windows Defender)

A solid and functional antivirus tool that is built into the latest versions of Windows. It’s straightforward to set up, never tries to sell you on any premium features, and integrates nicely into the Windows UI.

Windows Security offers both real-time protection, and on-demand scanning, but it is largely designed to stay out of your way, and only attracts your attention with the built-in Windows notification system if it ever needs to alert you of something. It doesn’t offer any built-in firewall functionality, instead leaving that to the Windows Firewall tool.

Perhaps the biggest downside of Windows Security is that it is extremely popular. Because it comes with Windows as standard, it’s extremely widely used. That makes it appealing for nefarious hackers to build malware and viruses that are specifically designed to slip past Windows Security. Microsoft does a great job of keeping it updated to take care of the latest threats, but it is a constant game of cat and mouse.

We generally consider Windows Security to offer a good baseline of functionality that will be perfectly capable of protecting you against the most common threats. It’s straightforward to use and setup, and it’s got a simple and intuitive UI. We don’t suggest relying on Windows Security alone, but it makes sense to use it in conjunction with another antivirus software.

If you have Windows 10, you can access Windows Security from the start menu.

Kaspersky Security Cloud Free

Widely regarded by many to be the gold standard for antivirus software, Kaspersky Security regularly scored the highest in tests for catching the widest range of malware and viruses. The free version is missing a few advanced functionalities compared to the paid version, but it is still a very comprehensive antivirus package that will be adequate for the majority of users. Kaspersky antivirus software has been around in some form since the late 1980s and has a long-standing reputation for being one of the best antivirus software packages around.

One feature you will be missing out on is the “Safe Money” feature, specifically designed to protect financial information, but this is just a nice extra feature to have, not an essential feature. Some other customizable options are hidden behind the paywall, but you can get by fine without them in most circumstances.

It offers real-time web protection by featuring malicious URL blocking, on-demand scanning for detecting infected files, and will automatically update its virus definitions in the background.

It is straightforward to use, offers comprehensive protection, and performs scans quickly and reliably. This is a capable security suite that in this free version is a great option for typical internet users.

You can get Kaspersky Security Cloud Free on Windows, but it is also available for Android and iOS.

Bitdefender Antivirus Free Edition

Another excellent performing antivirus tool, the free version of Bitdefender Antivirus offers you an excellent virus scan and will adeptly block malicious URLs when you’re web browsing. The scan offered here is top class, but there are some nice advanced features you will be missing out on without stumping for the paid version.

The free version is missing any firewall functionality, so you will have to look elsewhere if that’s something that you need. You’ll also be missing out on protection against malicious macros, and unless you upgrade, you won’t be getting access to their advanced Intrusion detection system.

This is a powerful antivirus tool, and if you pair it with a well-configured firewall, it should help to protect your system against the most common types of malware attacks.

You can get Bitdefender Antivirus Free Edition for Windows, but it is also available for MacOS and Android.

Avira Free Antivirus

Avira is a solid choice for checking your system and files for viruses. It does not offer real-time web protection, but it is adept at scanning incoming files for any malicious code. Along with Kaspersky Antivirus, this is one of the longest-running antivirus programs going, with its first release dating back to the late 1980s, and throughout that time Avira has been an excellent choice for virus protection.

There is also a paid version, which adds functionality such as integrated email security, real-time web protection.

The scans by Avira are generally not quite as bulletproof as some of the other free antivirus solutions, and it is fairly slow at performing scans. We wouldn’t pick this as our first choice, but it’s a good backup if you encounter any trouble with different antivirus tools.

You can get Avira Free Antivirus for Windows, but it is also available for macOS, iOS and Android.

Malwarebytes Free

Rather than working as a traditional antivirus, which would seek to prevent you from getting an infection in the first place, Malwarebytes is focussed on finding and rooting out any malware that has already infected your system, and removing or otherwise uninstalling it. It’s a great clean up tool for anything that has slipped past the net. We recommend installing and using this in addition to any antivirus software you install and running it on a semi-regular basis to double-check your system is completely clean of malware.

You can get Malwarebytes Free for Windows, but it is also available for macOS.

Since these tools are all free, there’s no harm in trying each of them and seeing what works best for you. You can even use more than one of them in conjunction with each other if you want to be extremely secure, or if one is missing some functionality that another provides. With these free antivirus solutions, you can rest assured that your system will be protected against the vast majority of malware attacks.