That’s because the free versions use exactly the same ‘engines’ as their paid-for counterparts. It’s not a scam, either. When you pay for antivirus software, you tend to get extra features beyond protection from viruses and companies seem to be happy to give away the antivirus part for free. This is why using the term ‘antivirus’ can be misleading. Antivirus is just one component of a comprehensive 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. Most of the software here is available for Windows, macOS, Android and iOS, though you tend to see fewer features on iOS in particular. Windows users tend to get the most, but because this is all free, you can install it on as many devices as you like. Windows comes with Defender and it’s just as capable as (if not better than) the protection you get from some paid-for antivirus apps. It’s certainly the easy option if you use Windows, but it doesn’t have some of the extra features you get elsewhere such warnings of fake websites that might try to steal your login details and, ultimately, your money. If you want the comprehensive protection and support a paid-for version includes, you’ll find recommendations in our best antivirus roundup. But if your looking to save as much money as possible, here are five free options. All work on Windows, but not all also have apps for macOS, Android and iPhone – only some do.

Is free antivirus really free?

Yes it is. But you may well trade off some privacy. Some companies may record, use or even sell information when you download and use their free product.

				Excellent protection					   					5GB VPN usage per week					 

				More limited protection for Android & iOS					 

It has a friendly, light interface which is easy to understand and use on all the devices it supports: Windows, macOS, Android and iOS. Although it also works on iPad, it’s really just the iPhone app scaled up. Windows and macOS get the lion’s share of features, though, with iOS the most limited. That’s standard, mainly because of the way iOS works. Underneath that new interface is the same excellent antivirus engine from Avast Free Antivirus, and it scores exceptionally well in testing by independent labs.  As well as blocking viruses, it’ll reliably warn you of fake websites (where you might inadvertently type your login details) and by default prevents ransomware from encrypting files saved in typical folders. There’s also a decent VPN built in which offers a generous 5GB per week of bandwidth. Quite a few big-name, paid-for security suites offer less than that, so for free, this is great. The bad news is you can’t pick from the list of 35 countries available in Avast One Premium. It just connects to the fastest location, which is usually in your own country, so it won’t unblock websites or streaming services for you. Essential will check specific email addresses and tell you if they’ve been included in breaches,  but to monitor an address and get alerts, you’ll again need to pay for Premium. However, limitations are inevitable: Avast can’t give absolutely everything away for free and what you get with One Essential is surprisingly generous. It’s our new top pick for free antivirus software. Get Avast One Essential

				Great malware protection					   					Some useful extra features					 

				Interface could be a bit friendlier					 

Regardless, AVG’s free offering include antivirus, ransomware protection, and will stop other forms of malware such as spyware.  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 antivirus duties, AVG also warns you of unsafe web links, and can block unsafe email attachments. As the greyed-out tiles attest to, you’re not getting the same level of protection as if you were paying for AVG Internet Security, but for free you can’t really complain. In independent lab tests, AVG scores very well. It achieved a perfect 18/18 in AV-Test’s most recent report, for example. Unlike Avast One Essential, there’s no VPN so although this is still a decent option if you’re after free antivirus, there’s better available these days. And like Avast’s free version, AVG’s is available for Windows, macOS, Android and iOS. Get AVG Free AntiVirus here.

				Scores top marks in independent tests					   					Doesn't ask for any personal details					 

				Lots of features require an upgrade to Prime					 

There’s a paid-for version called Avira Prime, but the free version uses an identical malware detection engine which has previously received top marks from two of the big virus testing houses: AV-test.org and AV Comparatives. But as soon as you start using Free Security you’ll realise why it doesn’t appear higher up in this list. It seems designed solely to nag you into upgrading to Avira Prime, with features seemingly available, but when you click on them it’s just an advert for Prime. If you can live with this, and many people will – not many people open up their antivirus app on a daily basis – then it’s nice that you don’t have to hand over any personal information at all – not even an email address – which is rare in this day and age. Avira clearly states on its website that it doesn’t sell data and never will. There’s also a Mac version, reviewed on our sister site Macworld, plus Android and iOS versions so you can protect all your devices for free. Get Avira Free Security here.

				Amazing malware protection					   					Phishing protection included					 

				No ransomware protection					   					Only for Windows and Android					 

The Free edition provides the same antivirus protection as in Bitdefender’s paid-for packages. Even the interface is the same, but as with others here, you’ll find padlock icons over some features or pop-ups telling you that you need to upgrade to use those features. So, the core real-time and on-demand malware is there, including Advanced Threat Defence and Online Threat Protection but not a whole lot else. One feature you might miss is Ransomware Remediation and although Bitdefender will attempt to block malware being downloaded as you browse the web – without having to install a specific web browser extension – it can be a bit hit and miss as to whether it’s successful or not. It’s far better at warning you of fake websites that might try to steal your login details, though. Bitdefender does offer a separate free antivirus app for Android, but not for macOS or iOS.

				Class-leading malware protection					   					Built into Windows					 

				Won't protect your non-Windows devices					   					Lacks additional protections found elsewhere					 

Wrong. In the latest SE Labs report, Windows Defender placed second overall, beating eight paid-for antivirus programs. AV-Test also found that it detects and protects against almost all attacks just as effectively as others. Performance of any antivirus software varies from month to month, but Defender has an excellent track record.  The fact that it’s already protecting your Windows devices if you haven’t installed any other security software is very convenient, too. 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 configure these – they’re not enabled by default. But that’s true of some rival products too. 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. Bottom line: you could do a heck of a lot worse than Microsoft Defender. 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. If any of this concerns or bothers you, then take the time to read the privacy policy before you install a product. This applies to paid-for products too, but on the whole they do not take liberties with your privacy. 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.

Do you really need antivirus on Windows?How to remove a virus from WindowsBest antivirus software for WindowsBest antivirus software for AndroidBest antivirus dealsBest VPN services (plus free options)Best VPN deals

Jim has been testing and reviewing products for over 20 years. His main beats include VPN services and antivirus. He also covers smart home tech, mesh Wi-Fi and electric bikes.

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