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The best antivirus software 2021

The words 'best antivirus software' next to a laptop PC
(Image credit: Future)
PRICE
VERDICT
REASONS TO BUY
REASONS TO AVOID
VERDICT
REASONS TO BUY
REASONS TO AVOID

Getting the best antivirus software is the first step to staying protected online. It's the strongest defense against the cybercriminals who want to expose your online devices for their own financial gain.

The way that viruses behave and their end goal has changed over the years, but generally the purpose is the same - to steal your money. Threats come in many forms, but malware, ransomware and Trojans are generally designed to either take your data or do enough damage to your system that you'll pay a high price to reverse the effects. And then there are outright scammers...

We're not trying to scare you and, since you’ve come to this page, you probably already have a fair idea why virus protection is such an essential tool. Thankfully, 2021's best antivirus providers combine watertight protection, extra features to keep you safe from scams, and are easy to install and use.

If it's free antivirus that you're after, we have some top recommendations for you, too (as well as some top business packages). But considering some of the best antivirus providers out there cost less than $10 / £10 / AU$20 per year, we’d always recommend playing it safe and paying for protection as you head into 2022.

Today's best antivirus software is Bitdefender

Today's best antivirus software is Bitdefender
You may be more familiar with names such as Norton, McAfee and AVG – but at the moment, we think Bitdefender is the best antivirus available. It combines watertight security tools with an array of other excellent security features. It’s also really easy to use and, best of all, offers extremely good value for money.

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The best antivirus software of 2021:

Bitdefender offers the most accurate and reliable protection around and has received several awards. (Image credit: Future)

1. Bitdefender Antivirus

2021’s best antivirus offers rock-solid virus protection and features

Specifications
Operating system: Windows, Mac, Android, iOS options
Maximum devices covered: 10
Stand out features: Safepay banking protection, privacy tools, multi-layered anti-ransomware, VPN
Reasons to buy
+Excellent core virus protection+So many features available+Safepay banking protection+Superb value for money
Reasons to avoid
-Minor ransomware clean-up niggles

Bitdefender is top of the tree as TechRadar's best antivirus, beating some stiff competition and doing so without asking all that much in terms of subscription costs – the basic plan really isn’t what anybody would call expensive. 

TechRadar Editor's Choice logo

Of course, being affordable wouldn’t mean anything if Bitdefender was at all shaky with respect to the core malware protection it delivers, but that isn’t the case. We found it to be excellent in defending against malware during our Bitdefender review, albeit with very slight caveats when it came to the exact way of dealing with some test ransomware threats. Nothing that threatened our security though, and this antivirus once again received a top rating from AV Comparatives for its prowess in dealing with advanced threats.

The sheer amount of features incorporated with Bitdefender is seriously impressive. Even the entry-level Bitdefender Antivirus Plus product provides excellent web protection and top-notch defenses against phishing and malicious links in general.

You get Safepay online banking protection, which is essentially a secure browser and one which covers you from all kinds of angles – it’s a real strong suit here. There’s also a password manager, which is a solid effort, and a vulnerability scanner which has been improved in the 2021 version of Bitdefender Antivirus Plus. Oh, and a good quality VPN is provided, albeit with a catch: a 200MB daily traffic limit. Still, it could come in handy for occasional use in a pinch.

Bitdefender is brilliantly user-friendly, with a polished and well-balanced interface that’s equally suitable for complete beginners to the antivirus world, or experts who want to tweak things.

The company offers more extensive suites, too, with Bitdefender Internet Security providing all the above plus a firewall, a quality spam filter, and parental controls, plus privacy extras like webcam and microphone hijacking countermeasures.

As the flagship offering, Bitdefender Total Security comes complete with an array of PC maintenance tools, plus it supports Android and iOS devices as well as covering Windows and Mac machines.

Whichever version of Bitdefender you choose, you’re getting a whole lot for your money, particularly with Total Security if you’ve got a lot of different devices (or a family to protect). Plus that secure feeling of knowing you're being kept safe by 2021's very best antivirus software.

Bitdefender Antivirus Plus | 1 year |

Bitdefender Antivirus Plus | 1 year | $39.99 $19.99 | 50% off
Not only is this one of the cheapest deals, it's coming from the world's best antivirus provider. Bitdefender Antivirus Plus comes with the added bonus of a VPN and Safepay as well as boasting multi-layer ransomware protection. This constantly tracks any malware and records the cyberthreat's pattern to keep you secure online.

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Click here if you're in the UK | £16
Click here if you're in Australia | AU$28

Norton AntiVirus will protect your PC without being a system hog. (Image credit: Future)

2. Norton AntiVirus

Solid protection with genuinely useful features

Specifications
Operating system: Windows, Mac, Android, iOS options
Maximum devices covered: 5
Stand out features: Intelligent firewall, PC maintenance features, bundled backup tool with online storage
Reasons to buy
+Loads of features+Useful bundled backup tool+Highly impressive browsing protection
Reasons to avoid
-More performance impact than top rivals 

Norton AntiVirus Plus is a sterling antivirus software app from the security company now known as NortonLifeLock. The main attraction here is the absolute stack of features you get, even with the entry-level antivirus product – not to mention the quality of those features.

They include a really useful intelligent firewall, which is a genuinely big help in terms of policing your system, along with some very thorough browser protection measures to keep you safe on the web.

There are also extras you don’t normally get with other antivirus applications, including a bundled backup tool which offers 2GB of online storage (it’s very user-friendly, too, ensuring that backing up is a breeze), and some useful PC maintenance utilities.

The package’s central antivirus defenses are tight, as we found in our testing, and as evidenced by the independent test labs (albeit with slightly mixed results from one of those labs).

The slight disappointment here, however, is that in our latest evaluation, we found that Norton is a bit heavy-handed when it comes to eating up system resources. Furthermore, Norton came near the bottom of the pack in AV-Comparatives' latest performance rankings – surprising as well as disappointing, seeing as in previous years Norton has done very well in this department.

Still, under normal operation, you likely won’t notice much in the way of performance slowdown, and you’re certainly getting a strong feature set for the money when purchasing Norton AntiVirus Plus.

If you want more then NortonLifeLock offers a range of higher-level suites. Norton 360 Standard adds some nifty extra bits of functionality, including an integrated full VPN service, more backup storage (10GB) and dark web monitoring (for some countries, including the US and UK). There are also strong mobile apps for Android and iOS.

However, if coverage for more than one device is required, then you’ll need to step up to Norton 360 Deluxe – this grants protection for up to five devices, along with even more backup space (50GB) and an in-depth system of parental controls.


Kaspersky Anti-Virus is comprehensive and easy to use without alienating more expert users (Image credit: Future)

3. Kaspersky Anti-Virus

A no-nonsense product that provides first-rate protection

Specifications
Operating system: Windows, Mac, Android, iOS options
Maximum devices covered: 10
Stand out features: Highly configurable virus scans, anti-ransomware, drive-by cryptomining infection prevention
Reasons to buy
+Very strong antivirus engine+Fast and configurable virus scans+Impressive anti-ransomware capabilities
Reasons to avoid
-Not a huge amount of features

Kaspersky Anti-Virus is this security firm’s entry-level offering for Windows PCs, providing coverage for up to 10 computers. It doesn’t bristle with as many features as some of the products on this list, but Kaspersky focuses on the security essentials, and does that job very well.

Its core antivirus capabilities are very strong, with Kaspersky ranking at or near the top in all the most recent reports from the big independent test labs. That’s great news, and our own testing fully bore this out with Kaspersky Anti-Virus performing very efficiently against ransomware, killing even unknown threats almost immediately and managing to recover the very few files which were affected by the attack. Kaspersky also benefits from some nifty self-protection routines.

Not much new has been introduced by Kaspersky in the last year or so, and so one downside here is that - as we mentioned at the outset - there weren’t a massive amount of extras in the first place.

Some of those additional capabilities aren’t hugely useful either. Kaspersky’s various ‘wizards’, for example, leave much to be desired, and the browser configuration one only supports Internet Explorer (not even Edge, let alone Chrome which is the most popular browser by far). There’s a bundled VPN, but it’s very limited (no location choice, and a 200MB daily allowance), although it could still come in useful in a tight spot.

The good news is that when it comes to extras, the bigger suites bundle more interesting functionality. Kaspersky Internet Security introduces an intelligent firewall (which hardly ever bothers you with any queries), plus a secure browser, and it offers coverage for Macs, along with Android and iOS mobile devices.

Kaspersky Total Security brings in more on top of all that, including smart parental controls, a fully-fledged password manager, and automated local (or Dropbox) backups. Those are some useful extras, and given that usually (with discounts) Total Security doesn’t cost much more than Internet Security, it’s likely worth grabbing unless you really don’t need those additional benefits.


Trend Micro Antivirus offers solid protection and is a delight to set up and use (Image credit: Trend Micro)

4. Trend Micro Antivirus

Accomplished fire-and-forget antivirus software solution

Specifications
Operating system: Windows, Mac, Android, iOS options
Maximum devices covered: 10
Stand out features: Ransomware monitoring, Pay Guard banking protection, high-quality URL blocking
Reasons to buy
+Strong antivirus engine+Impressive anti-ransomware performance+Very user-friendly
Reasons to avoid
-Not as many features as some rivals-Limited configurability

Trend Micro Antivirus+ Security offers simple but effective protection, with a user-friendly interface that spells out its various options in plain English without resorting to confusing jargon.

The app’s antivirus engine is rated very highly by the main independent test labs and has achieved some excellent results in recent evaluations – with the slight caveat that some testing found it raised a few more false positives than the top competition. We didn’t find this problematic in our Trend Micro review, though, and moreover, we observed that Antivirus+ Security’s anti-ransomware protection was a particular strength.

Another strong suit is the fact that this antivirus is currently top dog when it comes to blocking phishing sites (according to AV-Comparatives), and it provides great web browsing protection including Pay Guard as a secure environment for the likes of online banking.

Weak points? Well, system performance is impacted more than some rivals, and there aren’t as many options or features as some of the competition – this is an app more targeted at novices rather than experts. However, you do of course get more functionality with the higher-level security suites from Trend Micro.

The next tier product, Trend Micro Internet Security, throws in some interesting extras including parental controls and social media protection tools. However, for most folks, it’ll be worth spending a bit more on Trend Micro Maximum Security, which delivers protection for Mac and mobile devices as well as Windows (plus it adds a password manager and secure file vault).

There’s also a new Premium Security Suite, which covers up to 10 devices (you get 5 with Maximum Security) and throws in a free VPN along with a full tech support service.


Avira is a strong antivirus  - and our exclusive price makes it even more attractive (Image credit: Avira)

5. Avira antivirus

Solid security with a remarkable exclusive price

Specifications
Operating system: Windows, Mac, Android, iOS options
Maximum devices covered: 25
Stand out features: Proactive anti-ransomware, software updater, web protection
Reasons to buy
+Great value with our exclusive deal+Impressive anti-phishing and web protection+Configure as you like it
Reasons to avoid
-Ratings from some independent test labs are a concern

In truth, Avira is probably best known for its Avira Free antivirus option (which is among the best out there - see further down this page), but its premium packages should not be sniffed at – especially when you consider the incredible price you can now pay for its Antivirus Pro package.

That’s the name of Avira’s entry-level antivirus and it includes everything you’d expect of a modern-day security app: real-time scanning for malware, dedicated defenses against ransomware, a software updater feature that works very nicely to keep all your apps secure, plus various privacy tools including a file shredder for extra confidentiality.

The interface has been given a smarter and fresher new look for 2021, which is good to see, and the various features – including the free (but limited to 1GB monthly) VPN – are now better integrated within the UI overall.

The caveat here is that the ratings of the antivirus engine from independent test labs are only middling at best – but the app does provide a decent enough level of protection.

Upgrading to the Internet Security or Prime plan adds further features like a full password manager, and the Pro version of Software Updater (which provides automatic updates for your apps), plus Prime gives you the unlimited usage version of the VPN and mobile app support.

However, for the super-cheap price that you can now get Antivirus Plus, this certainly represents the best value proposition – indeed you’re barely paying more than for the free version, making this a seriously tempting choice.

EXCLUSIVE: Avira Antivirus Pro | 1 year |

EXCLUSIVE: Avira Antivirus Pro | 1 year | $44.99 $9.99 | 78% off
Simply put, premium antivirus doesn’t come cheaper than this. TechRadar readers (and TechRadar readers alone) now have the chance to pick up a year of award-winning internet security for less than $10. What’s more, if you decide that you don’t like it within the first 30 days, you can get a refund thanks to Avira’s money-back guarantee. A real bargain.

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Click here if you're in the UK | £29.99 £7.99

Webroot SecureAnywhere AntiVirus is extremely undemanding without compromising on protection  (Image credit: Webroot)

6. Webroot SecureAnywhere AntiVirus

A tempting lightweight antivirus option

Specifications
Operating system: Windows, Mac and Android options
Maximum devices covered: 10
Stand out features: Identity theft protection, real-time anti-phishing, firewall monitor
Reasons to buy
+Very well-featured+Incredibly streamlined app+Superfast virus scans
Reasons to avoid
-Limited testing data from independent labs

Just about every antivirus tool claims to be ‘lightweight’, but Webroot SecureAnywhere AntiVirus really delivers on this front. Installation takes seconds, and it only uses a tiny amount of drive space – plus the app’s memory footprint is just as minuscule, with virus definitions stored in the cloud.

Considering this, there’s still no compromise on features, which makes Webroot all the more impressive. You get extremely quick virus scans, along with a smart ‘firewall’ monitoring system, accurate real-time anti-phishing, identity theft protection and much more.

SecureAnywhere AntiVirus isn’t ranked by the big-name testing labs, save for SE Labs, which in its most recent Home Anti-Malware report rated Webroot as solid in terms of malware protection – although not quite up there with the top competition.

Further up the Webroot range, SecureAnywhere Internet Security Plus expands coverage from Windows and Mac PCs to mobile devices, also providing a password manager (courtesy of LastPass) and covering up to five devices (rather than three).

And at the top of the tree is Internet Security Complete which introduces an automatic backup tool (with 25GB of secure cloud storage) and additional online privacy features. There’s also a Family Pack version of the flagship suite which ups device coverage to 10 pieces of hardware, and provides 100GB of cloud storage.

SecureAnywhere AntiVirus gives you everything you need, really, although Internet Security Plus is our top pick for the most rounded package. And another boon worth bearing in mind here is Webroot’s confidence-instilling lengthy 70-day 100% money-back guarantee.


The famous free antivirus has a fantastic paid-of version in Avast Premium (Image credit: Future)

7. Avast antivirus

Heartily well-featured security suite

Specifications
Operating system: Windows, Mac, Android, iOS options
Maximum devices covered: 10
Stand out features: Ransomware Shield, Real Site DNS hijack prevention, Wi-Fi Inspector
Reasons to buy
+Plenty of features+Highly configurable+Capable firewall
Reasons to avoid
-May slow down your PC more than rivals-Web protection isn’t up there with the best

Avast’s Premium Security adds a whole load of features on top of the firm’s famous free antivirus offering. That includes – but isn’t limited to – a capable firewall, a file shredder, plus a useful Wi-Fi Inspector that keeps an eye on your network for vulnerabilities.

There are privacy-related tools like a Sensitive Data Shield which helps find and protect files that contain sensitive personal details. And a software update feature is also on hand to ensure that your applications are patched up to date (and therefore secure).

Premium Security is very smart in terms of being configurable, too, and it gives you a high level of control over the installation process, that's certainly welcome.

On the flipside of the doubloon, Avast has a bit more of an impact on system performance than many rival antivirus apps, and its malware scan times are also a little sluggish compared to some. Anti-phishing countermeasures aren’t as effective as the top competition, either, but having said that, the core virus protection delivered here is robust enough, and Avast performed pretty well in the latest round of testing by the independent labs.

Avast Ultimate is another option, which gives you Premium Security bundled with Avast’s SecureLine VPN and some PC clean-up tools thrown in. Avast’s VPN isn’t the best out there, but it’s a solid offering, and if you need that and an antivirus suite, the Ultimate package could make sense from a value for money perspective (depending on exactly what you need from your virtual private network).


(Image credit: Future)

8. Sophos Home

A great choice for multi-device protection

Specifications
Operating system: Windows and Mac
Maximum devices covered: 10
Stand out features: Central management console, AI-powered threat detection, advanced ransomware protection
Reasons to buy
+Capable antivirus engine+Great value for protecting a lot of PCs
Reasons to avoid
-Lack of options-Clunky interface in some respects

Sophos Home Premium covers (up to) an impressive 10 devices (Windows and Mac computers). It’s designed with novices in mind, which is no bad thing, although experts may find the interface oversimplified, and be disappointed that there are few options or low-level tweaks on offer.

The UI is also rather clunky in some ways – although that said, the web management console could be great for those who wish to take control and manage their non-tech-savvy family members’ devices.

Sophos provides capable virus protection, and worked well in passing our own anti-ransomware tests. For the antivirus software on offer – and given the 10 device ceiling – Sophos Home Premium could work out as a great value proposition for those who want to protect multiple computers.


ESET NOD32 Antivirus might lack in features but it offers powerful virus protection (Image credit: Future)

9. ESET Antivirus

Expert-level antivirus for the more experienced user

Specifications
Operating system: Windows only
Maximum devices covered: 5
Stand out features: Ransomware Shield, UEFI Scanner, Exploit Blocker, cloud powered scanning
Reasons to buy
+Supremely configurable, tons of options+Light on system resources
Reasons to avoid
-Some shaky results from independent AV labs-Not for novices

While ESET Antivirus and, in particular, its NOD32 plan doesn’t have all that many features, it’s highly configurable. Beginners will find it a tricky program to work with in some ways, but experts will love the level of control available here.

Furthermore, the streamlined program’s slender system footprint is another major plus point too. It also boasts some of best heuristic detection around, as well as some quality URL filtering.

Do bear in mind, however, that some of the independent testing labs have produced slightly worrying reports showing that ESET’s protection is a bit shaky, but others have come to more positive conclusions.

ESET does have higher-end packages in the form of ESET Internet Security and Smart Security Premium, and they add a good mix of features, but some of those extras are underpowered – and on balance, NOD32 Antivirus represents the pick of the bunch.


McAfee Total Protection is the company's standard plan - you choose how many devices to protect (Image credit: McAfee)

10. McAfee antivirus

Well-featured antivirus suite that’s competitively priced

Specifications
Operating system: Windows, Mac, iOS, Android options
Maximum devices covered: 10
Stand out features: VPN, spam filter, intelligent firewall
Reasons to buy
+Loads of features+Bundled VPN with unlimited usage+Higher-end plans represent solid value
Reasons to avoid
-Antivirus engine isn’t up there with top rivals-Entry-level product only covers one device

McAfee takes an interesting approach with its security range, as all the offerings are variants of its core Total Protection product, with the main difference being more devices are supported at higher tiers. McAfee Total Protection Single Device is the entry-level antivirus product, and as the name suggests, it covers one device.

The good news here includes a commendably light system footprint, meaning that McAfee won’t use much of your PC’s resources. There are also a ton of features on offer, particularly for a baseline product, and even if not all of them are of the highest quality, you get a lot for your money. That includes an intelligent firewall, an integrated (TunnelBear-powered) VPN with unlimited data, a quality spam filter, secure file vault, and some PC speed-up options.

The main stumbling block here is that the antivirus engine itself is not the best out there – although some results from independent test labs come out better than others – but this has to be something of a concern. There’s also the fact that you only get a single device protected with the basic package.

If you want antivirus software coverage for more than one piece of hardware, you’ll need to purchase the Multi-Device package which supports up to five devices including mobiles (plus it provides identity theft protection, at least for US users). Then there’s McAfee Total Protection Family which ups the ante to 10 devices and further bolts on a fully-fledged system of parental controls.

The latter could be a tempting choice for those with kids to keep safe online, and given McAfee’s typical pricing – with Multi-Device and Family subscriptions not being much more than the entry-level product, after discounts – you’re likely best off going for one of these higher-tier plans


Antivirus FAQ

What is the best antivirus of 2021

We've tested all of the biggest names in internet security, we've found that the very best antivirus software in 2021 is Bitdefender.

It's a superb bit of software - from its entry-level Bitdefender Total Protection and its cast-iron malware defences, excellent threat detection and genuinely value-adding extra features, right up to its all-singing, all-dancing Total Security that adds an array of maintenance tools and can be used to protect your family's computers, tablets and phones.

Do I really need antivirus in 2021?

The short answer to this question is yes, you really should have an antivirus app installed.

You may have heard arguments that if you’re very careful about where you browse on the web, and what you download or click on, you’ll be fine – and that’s true to a certain extent, but we really wouldn’t risk it. Even well-known websites might occasionally be victims of malware being peddled via their adverts (in other words, the ad networks they work with), for example, so no matter how cautious and tech-savvy you are, it’s worth having an antivirus app as a fall-back defense.

How do I choose the best antivirus software?

The obvious answer is staring you in the face...quite literally! Consult our rankings in this article, which is based on our expert knowledge and thorough, continually updated reviews of the top antivirus players.

That said, obviously you also have to bear in mind your own particular needs. Our number one pick might not be the ideal choice if you’re on a very tight budget, for example, and you only want to protect a single PC. Or at the other end of the scale, maybe you have a large family with a ton of devices to protect, and you need a package to cater for that. Or maybe you want a VPN service as well as antivirus, so a bundled package will save you a lot of money on subscription fees.

In short, our recommendations are here as firm guidance, but modify these appropriately based on your individual requirements. For more thoughts on this, check out our article exploring how to choose the best antivirus

Antivirus Software

(Image credit: Shutterstock)

What does antivirus do? How does virus protection work?

An antivirus app sits on your device like a guard dog, watching over the entire system and sniffing out any intruders (malware, or indeed anything suspicious). In short, it offers real-time defenses against viruses or other threats, which if detected are immediately dealt with, preventing them from carrying out their destructive payload. As well as this automated protection, you can run manual virus scans whenever you wish.

Antivirus applications use what are called virus ‘definitions’ to catch intruders. Think of these as the fingerprints of malware, and if something is spotted coming onto your system that has a matching fingerprint, the antivirus leaps into action, quarantining the offender. As another line of defense, antivirus programs also use what are called ‘heuristics’ that look for any file or process exhibiting suspicious behavior – this allows the app to potentially catch any freshly made malware which isn’t yet in its definitions database.

For more details on this topic, see our full breakdown of exactly how antivirus software works.

Is free antivirus enough?

The answer to this one isn’t straightforward – it’s a bit of a ‘yes, but no’ kind of reply.

A good free antivirus – like the ones we recommend on this page below – is a perfectly reasonable option for protecting your PC. It’ll do the basics of defending your system well, as any reputable vendor uses the same virus protection engine – the central tech that polices the device and repels malware – as the paid product.

That said, premium antivirus programs offer extra features above and beyond the fundamentals. A robust system of parental controls could be a huge win for those with kids, for example. Or a dedicated anti-ransomware layer of protection that only comes with the paid-for product could help catch one of the most dreaded infections and halt it in its tracks.

Given how cheap some premium antivirus apps are - particularly with the various deals on offer - it’s well worth considering going this route instead to get extra features that could give you more peace of mind.

For more on this, read our full piece on whether free antivirus is enough to protect you. Or just keep scrolling as we reveal today's best free antivirus software providers...

Best free antivirus downloads

Paying for a premium service means you get more features like spam filters, parental controls, system scans and advanced firewalls. This makes them more suitable for power users, those who want a bit of extra security and anyone who needs their system to run as smoothly as possible.

It also means you avoid annoying pop-ups that try and tempt you to upgrade to the full version. And, as you've discovered above, they won’t cost you an arm and a leg.

In fact, these days you can get top quality protection absolutely free, with just about every single major vendor out there offering a free antivirus. By doing so, developers gain access to more devices from which they can collect data, and therefore improve their knowledge and security platforms so it’s really not in their interest to reduce the amount of protection provided by the free version.

Windows has come a long way in terms of security, but it's still fair to say that Windows 10's built-in solution, Windows Defender, is the last free AV app you should trust to keep your system clean.

Avira Free Antivirus is today's best free security download

Avira Free Antivirus is today's best free security download
If you're determined to get free antivirus, we strongly suggest that you go for our pick of best security downloads - Avira Free Antivirus. We've highlighted its long list of features below, together with information on how well it performs at independent testing labs. A very impressive freebie.

Best free antivirus 2021 at a glance

  1. Avira Free Antivirus
  2. Bitdefender Antivirus Free Edition
  3. Kaspersky Free
  4. Avast Free Antivirus
  5. Sophos Home

Avira Free Antivirus

Avira Free Antivirus remains a superb free antivirus suite

1. Avira Free Antivirus

The best free antivirus for 2021

Specifications
Operating system: Windows, Mac, Android, iOS
Features: Virus detection, Phishing protection, Built-in VPN, System optimization tools
Reasons to buy
+Little impact on system performance+Great detection rates+Unexpected long list of features
Reasons to avoid
-Quite a few popups when running

Avira Free Antivirus for Windows continues to score highly on AV-TEST's stringent testing program, quashing 99.7% of tested threats, and it generally doesn't put too big a burden on your hardware. That's pretty good for a freebie, and why we have no qualms at all in naming it as our #1 best free antivirus download.

As well as the essential security smarts, we also love the clean, friendly interface and the fact it has a track record of throwing up minimal false positives. The introduction of a free security suite to optionally run alongside it – with anti-ransomware and a 500MB/month free VPN and various speedup promises – just sweetens the deal.

In fact, the list of features reads more like a fully paid premium package. It throws in identity protection, a password manager, anti-scam protection to prevent phishing attempts, and even a PC cleaner to keep your system spick and span.

If there's one thing we'd change then it's the tad overeager badgering - although popups and advertisements are very common to free products, and that doesn;t prevent us from wholeheartedly recommending Avira Free Antivirus.

Review and where to download: Avira Free Antivirus


Bitdefender Antivirus Free

Bitdefender Antivirus Free edition has taken the top spot in our free antivirus roundup. It's the best free security software you can download today

2. Bitdefender Antivirus Free Edition

Brilliant free antivirus from one of the best in the business

Specifications
Operating system: Windows, Mac, Android
Features: Phishing protection, Behavioural analysis, Automatic scanning
Reasons to buy
+Fast scanning+Excellent virus detection
Reasons to avoid
-Advanced users may want more control-Scans cannot be scheduled

Essentially consisting of the AV section of the full product, Bitdefender Antivirus Free Edition's clean, light, well constructed scanning mechanisms – which are almost universally faster than the industry average – and unrivalled virus definitions mean Bitdefender is a free antivirus force to be reckoned with.

The free version's insistence on running in autopilot mode is a double-edged sword, making the process of virus management easy but taking it out of the user's hands; while we're inclined to trust it, there have been cases in the past of automatic systems going slightly rogue, such as the incident a few years back when Panda Antivirus identified itself as a virus and locked up a large number of Windows systems. 

AV-TEST's testing did pick out a few flaws in its handling of zero-day threats, however. And it's worth pointing out that for you can currently get our top rated paid-for solution - Bitdefender Antivirus Plus - for the equivalent of around $2 per month. That's a tiny amount to pay for a tonne of extra features, such as online banking protection, integrated password manager, permanent file shredder and and free online 24/7 support. 

Review and where to download: Bitdefender Antivirus Free Edition


Kaspersky Free

The free version of Kaspersky's extremely successful antivirus software

3. Kaspersky Free

Supremely easy to use

Specifications
Operating system: Windows
Features: Real-time scanning, Anti-phishing, Email scanning, Spyware protection
Reasons to buy
+Accurate, reliable antivirus engine+User-friendly
Reasons to avoid
-Basics-only feature set-Limited technical support

The paid-for version of Kaspersky's Windows security software frequently tops charts of best virus prevention solutions and AV-TEST once again gave it full marks across the board in its latest round of testing.

As you would expect, Kaspersky Free is a scaled down version of the full program - a tool that we really like (more on which below). The free version ditches additional features such as privacy protection and safe payment sandboxes to concentrate on powerful, no-frills and - most importantly - free protection for your PC. The result is a tremendously easy to use and navigate bit of software that does an effective job of keeping you protected from viruses.

Using the nuts and bolts real-world scanning engine of the paid-for suite, Kaspersky Free is fiendishly hard for viruses and trojan horses to break down. And we love that it doesn't constantly pester you with nudges to upgrade to the full version.

But, ironically, we will just for a moment, because Kasperksy Anti-Virus isn't expensive to buy and yet affords much better protection to your PC (or PCs). The standard price is $29.99 to protect three computers and includes more muscle when it comes to preventing ransomware, spyware and Trojans.

Review and where to download: Kaspersky Free


Avast AntiVirus Free

Following its takeover of AVG, Avast now benefits from a much larger userbase, all reporting details of new security threats

4. Avast Free Antivirus

Lots of freebie extras

Specifications
Operating system: Windows, Mac, Android
Features: Virus detection, Gaming mode, Password manager, Malware scanner
Reasons to buy
+Doesn’t slow your computer+Great virus protection
Reasons to avoid
-Irritating privacy settings-Includes links to paid-for components

Avast and AVG haven't yet fully merged, despite the former formally acquiring the latter in mid-2016. The newly combined company says the two free antivirus products will remain separate, although there's apparently a joint AV package on the way soon. Obviously, though, Avast now has a lot more data to work with, having expanded its effective userbase (and, therefore, its threat detection network) to a whopping 400 million users.

The latest edition of Avast Free Antivirus adds an automatic gaming mode to mute popups and reduce system load when you're firing up a processor-hungry game, which is very handy indeed, and the interface has been given a clean new overhaul. There's a password manager, too, which is an undeniably good addition to your security portfolio.

It scores well on AV-TEST's widespread malware benchmark and continues a clean sweep against 0-day attacks – presumably that expanded detection network is really helping. Less impressive is the slight negative effect Avast has on software launch times, and its slightly popup-heavy attitude.

Review and where to download: Avast Free Antivirus


Sophos Home

Sophos Home delivers enterprise-level antivirus protection for home users

5. Sophos Home

A great choice for a home full of PCs

Specifications
Operating system: Windows, Mac
Features: Virus detection, Phishing protection, Parental controls, Protects up to 10 PCs
Reasons to buy
+Simple and non-intrusive+Good cloud-based control of protected devices
Reasons to avoid
-No scan scheduling-Limited controls for advanced users

Marketing itself as "business-grade security", Sophos Home does a little more than most free antivirus software, and actually seems better suited to families.

You get standard virus protection and anti-malware protection, along with browser tools like anti-phishing and, most importantly, content control. Combined with central management of up to 10 PCs, this means you can effectively lock down your kids' browsing options.

Although AV-TEST hasn't formally assessed Sophos' skills, fellow lab AV-Comparatives offers a decent rating of its abilities. 

Although Sophos Home has always had desktop notifications, there was no premium version of the software for it to encourage an upgrade to. That changed in February with the launch of Sophos Home Premium.

Review and where to download: Sophos Home


Head back up to read about our number one recommended best antivirus ^

Best business antivirus 2021

Each entry in this list has been carefully chosen for its business features, such as remote installation and central management. The best business antivirus software will have enterprise-level protection against threats, but that doesn't mean they have to cost a lot of money, either. The price per installation can sometimes be cheaper than even our recommended best antivirus packages.

1. Avast Business Antivirus Pro

1. Avast Business Antivirus Pro
An excellent business antivirus suite, giving you various tools such as virus protection,  Firewall, email protection, anti-spam and the ability to sandbox applications for complete security. Avast Business Antivirus Pro (as opposed to the standard Avast Business Antivirus) also includes Sharepoint and Exchange protection, as well as a number of tools for your servers.

2. Bitdefender GravityZone Business Security

2. Bitdefender GravityZone Business Security
This package makes reliable protection its top priority. Bitdefender products are loved by the independent testing labs, highly rated for malware detection, removal, performance and usability. Most of the features work automatically – anti-malware, firewall, web advisor, URL filtering – but you can also customise the product to control user actions.  

3. Symantec Endpoint Protection

3. Symantec Endpoint Protection
Symantec's first benefit is the company's Insight file reputation technology, an effective way to detect and block even the very latest undiscovered threats. Other layers of protection include virus protection, behaviour monitoring, intrusion protection, a firewall, and the 'Power Eraser' to remove stubborn threats and repair your system.  

4. Avira Antivirus for Endpoint

4. Avira Antivirus for Endpoint
This is Avira's main small business product. It takes all the core features you'd expect – antivirus, baseline network protection, web filtering – and extends them with file server protection and optimisation, along with application whitelisting and blacklisting.  

5. Kaspersky Endpoint Security Cloud

5. Kaspersky Endpoint Security Cloud
A small business product, which comes ready to protect Windows PCs, file servers, Android and iOS devices. The desktop side of the package has all the usual quality Kaspersky modules – antivirus, antispam, a firewall, more – but the mobile security technologies are even more impressive.   

Head back up to read about our number one recommended best antivirus ^

  • Even if you own the best computer in the world, you're still at risk

Mike began his career as a lead software developer in the engineering world, where his creations were used by big-name companies from Rolls Royce to British Nuclear Fuels and British Aerospace. He now covers VPNs, antivirus and all things security for TechRadar, although he still has a secret love of quirky open-source and freeware apps which find brand new ways to solve common problems.