Best Free Antivirus Alternatives to Windows Defender

The Windows Defender Security Center comes loaded on all Windows 10 devices, and it is quite good at its job. It isn't an enormous resource hog, it runs in the background quietly so that most of the time you won't even know it's there, and it doesn't bug you to upgrade to its full, paid versions. Many people swear you need nothing more than Defender, but others disagree. For anyone who wants a bit more protection without having to pay an arm and a leg, we rounded up the best free antivirus alternatives to Windows Defender.


Avast is a popular free antivirus option among our readers, and for good reason. It offers robust malware protection — PCMag's tests on Avast came back with a high malware-detection rate — while giving users a slew of extra options.

Those of you who live in apartment blocks or have many devices on the same network can take advantage of a network scan; Avast will essentially check out your entire network and any devices connected to it, and report back to you if it notices any security issues. After all, you might not have noticed that a random laptop was a part of your network, and who knows at that point what it's up to.

Add a password manager, phishing protection, behavior analysis, and game mode to the mix, and you have a great free antivirus alternative, especially if you're worried about network vulnerabilities.

See at Avast




Thanks to AVG's clever way of verifying the legitimacy of files — it checks signatures against its ever-expanding database of known malware — it received a perfect six out of six rating from independent lab AV-TEST in the usability department. TopTenReviews called AVG "the best free antivirus software" in its review.

On top of potent real-time protection, AVG also delivers some great add-ons, like email protection, a firewall that keeps away ransom hackers, and payment protection when shopping online. There is no quick scan feature — a bust for some of you — but you can direct it to look at specific files and folders. Overall, the scan is quite a bit faster than most other free options, especially after you've completed an initial scan.

Anyone looking for an able antivirus that can scan quickly and that has a lot of customizable options should consider checking out AVG. Although it was acquired by Avast in 2016, it is remaining an independent product for the foreseeable future.

See at AVG


Avira is a favorite among many antivirus users due to a combination of exceptional protection against malware and a bunch of free add-ons you'd usually only find in paid offerings. When it comes to actually protecting your computer, independent lab AV-TEST gave Avira a six out of six protection score — it doesn't get much better for pure defense against malware. Performance, or how much Avira will slow down your PC, also received full marks, making it one of the least-impactful antivirus alternatives you can find.

Having a low impact doesn't mean it works slowly, either. Anyone who hates watching the scan bar move slowly toward completion as you wonder whether or not your PC is infected will love how fast Avira's quick scan completes its job. Tom's Guide, in its review, said:

At 1 minute and 28 seconds, Avira's Quick Scans were more reasonable — in fact, among the fastest in the free category.

If you'd like some extra features, Avira comes with a few optional add-ons. Phantom VPN gives you 500MB of free data per month — you can browse the web securely knowing your data is encrypted, and you'll also have access to geo-restricted sites.

See at Avira



Sometimes PC users just want a solid product that doesn't come with a lot of bells and whistles. Enter Bitdefender. This free version of the full antivirus suite offers the same incredible malware protection you'd receive if you paid top dollar. Independent lab AV-TEST found a 100 percent success rate against malware attacks when it tested the product over two months, and it also came back with a perfect usability score. Tom's Guide calls it "one of the best antivirus programs available at any price."

Bitdefender checks signatures against those of known threats, ensuring your protection is always at the cutting edge. The user interface is no-nonsense due to its overall lack of features, but that might be what some of you are looking for — keep in mind that you can't schedule scans or do a quick scan.

Although the paid version of Bitdefender has all the features you'd expect from antivirus software, you won't be constantly pestered to upgrade while using the free version. Anyone looking for a free antivirus with a simple user interface, impeccable malware protection, and who doesn't mind a lack of features should definitely have a look at Bitdefender.

See at Bitdefender


Sophos Home

Sophos Home

Sophos has primarily been about protecting businesses from outside threats, so its free Home version offering a decent set of features is no surprise. It can protect you against phishing and malicious links, plus its remote access feature lets you check on your PC's health at anytime, from anywhere. PCMag, in its review, says:

Sophos Home Free gives home users much of the antivirus protection found in business security tools from Sophos, including remote management of up to three installations.

Setup is relatively easy, and once the app is installed and the antivirus definitions are updated, you can easily navigate settings through the intuitive user interface. Sophos is using the same highly-rated technology here as is found in its paid services, and independent testing labs, like AV-TEST give it great marks for security, performance, and usability.

See at Sophos



Malwarebytes isn't antivirus software. It is, however, used by a ton of people and was suggested by several of our readers as a great way to scrub your PC of anything that made it past the primary defense system. A 14-day free trial with all features is available, and after that you'll still get anti-malware, anti-spyware, and anti-rootkit tools.

The beauty of Malwarebytes is that you can use it alongside other antivirus software as a backup. It won't hog a bunch of your system's resources, and you can scan your PC anytime you want. There are also a couple of tools that let you delete locked files and registry keys for times when malware is embedded deep.

See at Malwarebytes

More great protection for your PC

If these free options above don't satisfy your needs, have a look at our list of the overall best antivirus software of 2018. There are plenty more options available there to keep your PC protected.

Updated July 12, 2018: I've refreshed this list to ensure you're still getting a top selection of free antivirus alternatives.

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