Six great free antivirus programs for PC, laptop and tablet. The best free antivirus for your Windows PC. (See also: what's the best security software?)

We show you how you can secure your PC or laptop without paying out a fortune. You will lose a little in terms of total security, but we're confident that these free tools will help to make your PC or laptop safe. The best performing internet security products from the likes of Norton and BitDefender offer best-in-class antivirus engines. But their principle benefit is additional features that help you secure data and make informed decisions about potential threats. You can get by with free alternatives. There is an additional risk, but a major cost saving. 

Every Windows PC, laptop or tablet needs security software. And that should include an up-to-date firewall, antivirus and antispyware. That doesn't automatically make your PC secure, of course. Human behaviour is such that an online PC or laptop is never entirely safe - but solid security software is a good start, and it will protect you from all but the most sophisticated and well directed attacks. If you are prepared to pay, read our article: 13 best antivirus for PC and laptop: 2014's best antivirus for protection, best antivirus for performance, and best antivirus for value to get best value for money. But there's true value to be had in a freebie.

Here then is our list of the best free antivirus software, based on independent testing from

Computer Security

Best free antivirus - Malwarebytes Antimalware Free

We rate this 3.5 out of 5

We're going to start with a tool that should be part of any PC- or laptop's security arsenal. In general it is a very bad idea to run two lots of security software, as they will tend to identify each other as malware and then indulge in a fight to the death (with your PC as collatoral damage). But Malwarebytes Antimalware Free is designed to fun alongside other security software as an additional layer of security. So if you choose any of the free tools outlined below, why not run Malwarebytes alongside to pick up anything they miss?

Malwarebytes Anti-Malware Free isn't quite an anti-virus suite; it's not designed to be. Instead, it's written as an extra level of security, to help remove those stubborn infestations you may not even know you've got.

The full paid-for version of the Malwarebytes Anti-Malware Free suite includes a scheduler, so you can set it to run scans automatically, but the free version offers a manual scan only. You could run it regularly, or when you suspect you may have problems. 

Best free antivirus - Microsoft: Windows Defender

Score - 5 out of 10

Now we'll move on the true security software programs, one of which you *must* run if you want your PC or laptop to have anything like a long life.

We're not taking these in any order, but we have to start with Microsoft's own AV product. If you buy a computer running Windows 8 it comes with Windows Defender installed. Windows Defender in Windows 7, Vista and XP is a slightly different thing, but if you install the free Microsoft Security Essentials it adds the same level of protection. As an integral part of Windows it is easy to use.

So if Microsoft makes its own free Windows antivirus, why would you ever pay for security software?

Well, it's fair to say that the protection isn't the best on the market, although it is far from terrible. In's most recent tests Windows Defender picked up 99 percent of known threats, and in January 2013 it found 98 percent as against an industry average of 99 percent. More important are unknown or so-called 'zero-day' threats. Here Windows Defender 4.0 picked up only 82 percent of threats in January 2013, and dropped to 81 percent in February.

That's not a catastrophic result, but you should want better protection than that and the industry average is 95 percent. AV-Test awards Microsoft only 2/6 for protection, and we can't argue with that.

The story is better when it comes to system performance, where Defender gets 3.5/6. It wil have an impact on your PC's performance, and it's more of an impact than the industry average. But it won't cripple your PC. Indeed, with Windows 8 PCs one of the benefits of the better paid-for security software products is that by disabling Windows Defender they make your PC faster. An odd situation, but there you go.

Where Windows Defender excels is in false positives. Simply, in AV-Test's testing it never produced a single warning for a false threat. That puts it out ahead of virtually every other security software product.

Clearly, however, protection is the key factor. So overall we'd give Windows Defender 2.5 stars. It offers some protection, but not enough.

Windows Defender

Best free antivirus - Avast Free Antivirus

Rated 9 out of 10

Let's go alphabetical and start our look at third-party programs with Avast's Free Antivirus. Here the story is much more positive. Avast matches Windows Defender's decent performance result, and also fails to give any false positives. So far so solid.

But Avast offers much better protection than Windows Defender. Indeed, it offers great protection.

In tests Avast's Free Antivirus found 99 percent of all know threats, which is the industry average (including paid-for security products). More important is the way Avast deals with zero-day threats. In January it picked up 98 percent of unknown security threats, and in February 2013 100 percent, as opposed to an industry average of 95 percent. Kudos to Avast, to which AV-Test awards 5.5/6 for protection. That's good enough for us. We found Avast to be perfectly straightforward to use, so we'd gladly recommend this free software with 4.5 stars.

Avast Free Antivirus

Best free antivirus - AVG Anti-Virus Free Edition

Rated 8 out of 10

AVG is almost up there with Avast in terms of the all-important protection. In both January and February 2013 it detected 99 percent of the known threats thrown at it by That is the industry average. Critically, it picked up 98 percent and then 100 percent of unknown threats. Avast is just on top there, but AVG Anti-virus Free Edition's protection performance is excellent. AV-Test awards 5.5/6 for protection.

System performance better than that of Avast, however. AV-Test offers a decent score of 4.5/6, so if you have an underpowered PC this may be a good choice for you, given the protection score.

Finally, in terms of false positives AVG kicked up a handful over the two tests in January and February 2013, but nothing that would cause any concern. It's a great free product and we award 4 stars.

AVG Anti-Virus Free Edition

Best free antivirus - Check Point ZoneAlarm Free Antivirus + Firewall

Score - 7 out of 10

Check Point's ZoneAlarm Free Antivirus + Firewall antivirus program is another of the big beasts of the free security world. System performance is good once again, and AV-Test offers a performance score of 4.5/6. Even more impressive is the usability score - only Windows Defender has fewer false positives on test than does ZoneAlarm Free. So ZoneAlarm won't slow down your PC or spam you with false positives.

But will it help to keep your PC safe? It will - perhaps not as well as AVG and definitely not as well as Avast, but ZoneAlarm offers good protection.

In's January- and February 2013 tests ZoneAlarm found 99- and 100 percent of all known threats. Alas when dealing with zero-day threats it dug out only 91- and 93 percent of attacks. This is not terrible, but the industry average is 95 percent and AVG and Avast are both much better.

Good then, but not great. ZoneAlarm Free AntiVirus + Firewall is worth a look if you have a low-powered PC, but the protection offered elsewhere is better. We give it 3.5 stars.

ZoneAlarm Free

Best free antivirus - Panda Security Cloud Antivirus FREE

Score - 6 out of 10

One other free security program worth your consideration is Panda's Cloud Antivirus FREE. It's a good all rounder offering solid protection. In the January- and February 2013 tests it dealt with 100 percent of the known threats AV-Test pushed in its direction. It wasn't quite so good at dealing with zero-day threats, although it outperforms Windows Defender and ZoneAlarm, picking up 95 and 94 percent of threats over the two months. That's just about industry average.

Add to this an excellent usability score in which Panda failed to produce any false positives, and a decent performance score of 4/6 and you can see that Panda is a good free antivirus. We award 3 stars.

Panda Cloud Antivirus

Best free antivirus - extra protection

There are other free antivirus products that are worth considering as extra layers of security. You can bolster your free AV setup with one of Malwarebytes' Anti-Malware Free or Comodo Cleaning Essentials - both are good for cleaning up malware infestations after the event.