Protecting your PC, laptop and even your phone from internet threats is essential these days. It's no longer optional.
Many people would rather not pay for the privilege, and since you're reading this, you probably fall into that camp. While there are great deals available on paid-for security suites, it still amazes us that you can have the same antivirus component that's in Bitdefender and Kaspersky's Total Security packages for free.
So, after reading through our list of six recommended options below, there's no excuse for not running antivirus software on all your PCs and laptops. In some cases there's an Android app, too.
Should you get free antivirus?
The catch with free antivirus is that it doesn't always offer the most complete protection. It is better than having none at all but free versions tend not to include some of the extra features that come with paid-for products.
This is why using the term 'antivirus' can be misleading. Antivirus is typically just one component of a good security product, which can also include specific protection from ransomware as well as spam filtering, parental controls, password managers, VPNs and cloud storage. However, that's not to say those features can't be found in free products - you'd be surprised what you can get without paying or even handing over your email address.
If you want the comprehensive protection and support a paid-for version includes, you'll find recommendations in our best antivirus roundup.
Best Antivirus software reviews
Kaspersky Security Cloud Free
Kaspersky is a big name in antivirus, and it offers a free version for PC.
As you'd expect, this is pared-back offering. There's no parental control or online payment protection here. But it does now include a password manager and VPN (the same as in the paid version of Security Cloud). Another new feature is Account Check which can monitor your online accounts and alert you of any data leaks.
The core protection includes all the essentials, including file, email and web antivirus, automatic updates, self-defence, quarantine and more.
What's particularly good to see included is extensive right-click functionality against individual files. You can scan a file, send it to the Kaspersky Security Network to instantly have its reputation checked out.
You also have access to Kaspersky's cloud-based Application Advisor, which provides a full rundown about the content of the file, the number of users that have tested it, where in the world people are using it, along with various pieces of technical information.
In AV-Test's latest report, Kaspersky scored full marks for protection, performance and usability, which is especially reassuring.
There's also an Android version that includes antivirus protection for your phone, which similarly scored full marks.
Bitdefender Antivirus Free Edition
Bitdefender's free offering is simple, robust and reliable. Its paid-for version is one of our top two recommendations right now, too.
By simple, we really do mean simple. There are no modules here that turn out to be paid versions, no password manager, and no secure browser to install. This is stripped back system protection only, offering just antivirus and nothing else. However, Bitdefender's AV engine employs the same machine learning as the full version, enabling it to spot unknown threats as well as known ones.
The interface is similarly sparse. You can drag-and-drop files on to it to scan them, but you can also right-click them in Explorer and do the same thing without dragging. Any dodgy files are quarantined, and you can also set up exclusions - both files and folders - that will not be scanned. This is useful if Bitdefender should produce a false positive that keeps preventing an application from running.
Overall, being stripped back to just the essential antivirus function, Bitdefender Antivirus Free Edition is very simple to use, with good AI-based protection. It's lightweight, too, so won't slow down your computer.
Bitdefender scored 100% for protection in AV-Test's most recent report and it only lost half a mark for usability because of six false detections of legitimate software as malware during a system scan in October 2020.
As well as Windows, you can also get Bitdefender Free for macOS and Android.
Microsoft Windows Defender
Many people think Windows Defender isn't up to the task. Built into Windows 8 onwards, it runs by default when no third-party antivirus software product is installed. It's just a sop to appease Windows haters, right?
Wrong. AV-Test has found that it detects and protects against almost all attacks just as effectively as Kaspersky and others. As mentioned, performance varies from month to month, but it's still good to know that it's still doing an excellent job, and outscoring quite a few paid-for products' antivirus engines.
There's a common perception that Windows Defender has no toys in the box beyond basic antivirus duties. This is not the case. For starters, there's ransomware protection that allows you to nominate folders that cannot be changed other than with your explicit say so. Integrated OneDrive support allows you to recover files that do become corrupted by malware.
You have to set these things up, but you have to do this when you install rival products as well.
Suspect samples can automatically be submitted for thorough cloud-based analysis. Being tightly integrated with Windows also allows Defender to provide innovative sign-in options, including Windows Hello, which allows you to log in with your face or fingerprint.
There's also the integrated Windows firewall, advanced exploit protection, and protection from code being injected by malware into innocent processes.
Secure Boot prevents rootkits or anything else from running and hiding before other software, including AV software, gets a chance to start up. Scanning duties include an offline scan that runs at boot time, before Windows starts, thereby denying rootkits and other stealthy malware a place to hide.
Don't put too much stock into the parental controls baked into Windows, nor the VPN built into the operating system. It's very basic stuff, but it's also not really core to antivirus protection.
If you're lazy (and let's face it, we all are when it comes to security), you don't need to do anything if you only want to protect your Windows 10 devices: Defender is already running.
Bottom line: you could do a heck of a lot worse than Windows Defender.
Avira Free AntiVirus
Avira is a German company which has offered free antivirus software for as long as we can remember.
It has now given the interface a complete overhaul to make it simpler to understand and use, and in the Windows version in particular there’s a new Smart Scan option which checks for security, privacy and performance issues and resolves them with a single click.
Avira offers a paid-for version called Avira Antivirus Pro, but the free version uses an identical malware detection engine which has received top marks from two of the big virus testing houses: AV-test.org and AV Comparatives.
These results change over time. In the most recent AV-Test report from October 2020, Avira scored only 98.9% for zero-day malware (meaning unknown threats), which isn't ideal. However, that could well be back to 100% now - it has been consistently in the past.
The package also includes many of the features that are normally reserved for the paid-for product such as ransomware and phishing protection, a VPN (but only 500MB per month), a password manager, driver updater, file shredder, duplicate file finder and performance optimiser. There’s also the browser extension Browser Safety that you can install which protects you from phishing attempts and websites which contain malware, as well as blocking ads and preventing websites from tracking you.
Given that you don’t have to hand over any personal information at all - not even an email address - to get all this for free is rare in this day and age. It means that you’re not paying for antivirus by being the product yourself: Avira clearly states on its website that it doesn’t sell data and never will.
It doesn’t even share data with third parties, and it has dropped the pop-ups and banners (some would call ads) which existed in the previous version of Free Antivirus. There are, of course, upsells. If you want unlimited VPN data you can pay and - as with all VPN services - the prices come down if you sign up for a longer period of time. But you don’t have to sign up, and you can install a separate VPN service such as ProtonVPN will will give unlimited data for free.
Avira says its engineers are working on making it 'lighter' so it uses fewer system resources and more powerful still. Soon there will be a Mac version as well, but there are Android and iOS versions available right now.
Overall, this is a very well specified free AV product that can give paid products a run for their money.
Avast Free Antivirus
Unlike some some AV companies, Avast doesn’t hide its free antivirus offering so you can’t find it. It's prominent on the website's homepage, more so than even its paid offerings, so that's a good start.
Unfortunately, the company hit the headlines at the start of last year for collecting a surprising amount of user data, as revealed in this Vice article. It has since said it has stopped doing this.
As well as basic protection, Avast Free Antivirus offers defence from unknown threats using its Behaviour Shield, which stops even previously well-behaved software from suddenly performing dodgy operations that could endanger your identity and data.
There's also a handy password manager, so you can log into sites in your browser by remembering just one password. This is pre-stuffed at installation time with login details found in your installed browsers.
What's not so great is that the system Cleanup Premier tool is an advert for the paid version. It will tell you what's slowing and bulking your computer, but you'll need to “buy” a free 60-day free trial. Similarly, installing the VPN and enabling it opens an invitation to subscribe to the service for a monthly fee.
AVG Free Antivirus
AVG is now owned by Avast, so both products use the same engine and have the same level of protection.
AVG's free offering has antivirus, ransomware, spyware and will stop other forms of malware.
The greyed-out tiles on the home screen are basically adverts for the paid-for AVG Internet Security as they're not included, and you certainly get more with Avira's free offering.
AVG Antivirus Free offers six different scan types, including Deep Scan, USB/DVD scan, single file or folder scans, and a boot-time scan, which runs before Windows starts up, thereby running before any lurking malware has a chance to start up and protect itself from the product.
In addition to AV duties, AVG also warns you of unsafe web links, and can block unsafe email attachments. Rounding out the product is a handy file shredder, right-click scanning for individual files, and a Do Not Disturb mode, which allows you to play games or watch shows without nag screens or other notifications.
In the September-October 2020 report, AV-Test awarded AVG a 'Top Product' badge and it received a full six out of six marks for protection. It only lost half a mark (as did Avast) for its performance impact on Windows, so ultimately, there are better choices here.
Get AVG free here.
Is free antivirus really free?
Yes it is. But you may well trade off some privacy. For example, Avast and AVG’s privacy policies clearly explains how it uses your personal and non-personal information when you download and use its free product.
You might be asked if you want to opt in to data collection during installation of these products. This is why it is absolutely crucial you read what you're agreeing to when you install an app, and are extra careful to opt out of any data sharing.
Otherwise, you grant the software the right to share some of your (anonymised) information to third parties, which may include advertisers and other companies.
The danger is that a company might work out how to de-anonymise this data, which is a risk you don't want to take.
And some free antivirus products will be supported by adverts, typically on Android versions. You can find out if it's worth installing antivirus on Android and whether iPhones need protecting from malware or not.
And these days, antivirus software should comply with GDPR in Europe and with other privacy regulations in other countries.
Does free antivirus software work?
Privacy is perhaps not the most important factor, depending on your outlook. Antivirus software is designed to prevent your PC and laptop - plus phone and tablet - from being infected by malicious code which could cause issues ranging from annoying pop-ups through to stealing your personal information or even deleting or encrypting your files.
The effectiveness of antivirus software changes over time, and a product that stops all viruses today may not do that tomorrow or in a month. No antivirus software offers a cast-iron guarantee that it will stop 100% of malware, but many achieve this figure. And it's essentially the same virus protection you get from the paid-for version of that product.
So, yes. It works. It's not an excuse to start downloading cracked software or visiting dodgy sites though. Security requires a multi-layered approach, and that includes being careful and sensible about the sites you use, the links you click on and the stuff you download.