Best Free PC Antivirus Software

Windows PC users need a strong antivirus program to ward off malware attacks, to keep their computers running efficiently, and to safeguard their online identities and personal information. Paid antivirus suites have many features to protect children online, manage security on mobile devices, and monitor a computer's firewall, software updates and other features. But some users just don't want to — or can't — pay a yearly subscription fee for those extra features.

If that describes you, you've come to the right place. We've evaluated the most widely used free antivirus programs based on their malware protection, system impact, ease of use and useful extra features.

So which free PC antivirus product is right for you? Of the six free antivirus programs we reviewed, Avast Free Antivirus came out on top. It offers very good malware protection, has a small system-performance impact and includes features that rival those of midpriced paid antivirus suites, such as a password manager and a hardened web browser.

If you'd rather not fuss with settings, then try Bitdefender Antivirus Free Edition, which has even better malware protection but doesn't let you adjust (or do) much other than ward off threats.

How We Tested

To evaluate installation, ease of use, interface and performance impact, we installed each AV program on the same Asus X555LA laptop, which ran Windows 10 and featured an Intel Core i3-4005U processor, 6GB of RAM and 36GB of data on a 500GB hard drive.

We conducted our own tests on how much each antivirus product affected our laptop's performance, using our custom OpenOffice benchmark. We timed how long it took to run a quick scan and a full scan while the laptop crunched numbers in the background.

We also assessed how easy each program was to use, the number of useful extra features it offered (including free add-on software) and how insistently each program nagged us to upgrade to paid software.

Our malware-detection data comes from two independent evaluation labs: AV-TEST in Germany and AV-Comparatives in Austria. Each lab regularly tests major antivirus products for their abilities to detect zero-day malware and other threats.

Avast bought its rival AVG last year, and the two companies' malware-detection engines have been merged, with remarkable improvements. Avast Free Antivirus already had a friendly interface, a nearly imperceptible system impact and useful extra features, including a password manager and a network scanner. Now that its antivirus protection is almost perfect, we recommend Avast Free Antivirus without reservation.

Bitdefender's malware-detection rate is second to none. The company's free antivirus product covers all the basics and has a very low system-performance impact. But Bitdefender Antivirus Free Edition's bare-bones interface can be hard to figure out and offers few options — you can't even schedule a scan. It's best for users who want a set-it-and-forget-it security solution.

AVG and Avast are now part of the same company, and their unified malware-detection engine comes close to those of industry leaders such as Kaspersky and Bitdefender while having a light system-performance impact. But AVG AntiVirus Free got the short end of the deal, with fewer useful extra features than Avast Free Antivirus and misleadingly named new scans. The good news is that AVG's wide range of customization options is still available; the bad news is that you still get nagged to upgrade to paid AVG software.

Avira's malware protection has declined a bit as Avast's and AVG's have improved, which makes Avira Free Antivirus' heavy system-performance hit less tolerable. Its austere but option-packed interface can be intimidating at first, but it offers a high degree of customization. Avira does have a wide range of free add-on features, including a VPN client and a password manager. But be sure to read the fine print, because many of the best functions are reserved for paying customers.

Panda's malware-detection scores are better on Windows 10 than on Windows 7, and the company has a high rate of false positives, or benign files mistakenly flagged as malware. Panda's customizable user interface is gone, and its system-performance impact has grown. Worse, the software still tries to hijack your web-browser settings and won't let you opt out of system-data collection.

Windows Defender's once-subpar malware-detection rate has gotten better, but that doesn't mean you should rely on it just yet. The software, which is part of Windows 8.1 and Windows 10, still came in last among the six products we reviewed, and its high rate of false positives confirmed that ranking. Windows Defender has an inexplicably high system impact during full scans, and does nothing to protect non-Microsoft browsers from online malware. It also has nearly no extra features. Even if you don't want to pay for antivirus protection, you can do better than Windows Defender.

Honorable Mention

Malwarebytes Anti-Malware Free is not antivirus software. It can't protect a PC from infection, but it does an excellent job of cleaning out malware that's already on your system. Plus, it doesn't interfere with any antivirus software that's already installed. We recommend Malwarebytes Anti-Malware Free as a complement to any antivirus program.

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  • Paul NZ
    No you dont. I've never bothered with using a separate Av or firewall. I'm still here.

    They're all a waste of money. NOD32 is probably the only one worth getting. If I did use t
    -2
  • JazzAzz
    Why isn't ClamAv for Macs mentioned???
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  • James_397
    Anonymous said:
    Whether you're running Windows, macOS or Android, you need antivirus software. The question is what you want -- and how much you should pay.

    Best Antivirus Software and Apps 2016 : Read more


    Yet another silly thread. If you have Windows installed, use Defender... period. Stop listening to all the third-party marketing hype. There is no need for anything other than what comes with the OS.
    1
  • Audcurr
    I think customer service should be taken into consideration as well. Bitdefender is the worst, I bought it and the activation key wouldn't work, it took for ever to get it straighten out and they are quite rude.
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  • jackj59
    Fwiw, dealing with an issue now, of virus and/or malware, and after running bitdefender and it clearing what it found, I ran malwarebytes and it found over 10 more instances of malware. So though one shouldn't run live more than one at a time, I recommend having malwarebytes and run it periodically, too.
    1
  • jackj59
    Correction: including PUP's - from something called AnonymizerGadget - malwarebytes now found hundreds of more that bitdefender, avast and TrendMicro all missed when using their free online scan. And they aren't simply "potentially" unwanted programs, that AnonymizerGadget is defintely mal/spy/virus ware.
    1
  • Alan_K
    I'm curious about why you didn't test Norton Internet Security. Not that I'm advocating it; indeed I look forward very much to spitting on Symantec's grave some day and only found this article while looking for alternatives. (That was after I found that Norton charged me three times for two subscriptions last year because they set up two automatic deductions on one of the subscription accounts. They then refused to refund the double payment because it was out of the "60 day guarantee period". Burn. In. Hell, Symantec.) However given that Norton would have a not-insignificant market share I would have thought that it would have been one of the ones to test. I would have been curious to see how it performed.
    1
  • Paul NZ
    Yup most of them are a waste of money.

    Doesnt matter what you get. And if you're stupid enough to use programs like Utorrent and get dodgy programs.

    Whats the point in having one anyway. Any AV program doesnt detect everything. And your system will end up infected anyway
    -1
  • Bill_123
    For people who seem to think anti virus programs are waste of time if they go on the internet and they depend on windows to protect them I would say there is a 99.9 percent chance they are already infected with some form of virus or malware. I have found that the better ones are VERY hard to breach and although it is still possible to get a virus the odds are slim to none. Without them your almost guaranteed you will pick something up in short order is just a fact in the modern age. The biggest issues I have is how much do they impact computer performance and how good is their detection. Some are like dropping a boat anchor dragging your computer down some almost unnoticeable. So instead of spreading viruses to all your friends and family get a good virus program and save yourself and everyone you know a lot of grief.
    1
  • espressonator
    Why isn't there a comparison chart? I've used Avast for years; it's free, and it's very good. Why did not Mr. Tom mention Avast as either better or worse than these paid products? My guess is that Mr. Tom is really acting as an advertiser. If he were "non-partisan", then I think he would provide a comparison chart or so to explain why it's worthwhile to pay for products like this instead.
    0
  • Bill_123
    Anonymous said:
    Why isn't there a comparison chart? I've used Avast for years; it's free, and it's very good. Why did not Mr. Tom mention Avast as either better or worse than these paid products? My guess is that Mr. Tom is really acting as an advertiser. If he were "non-partisan", then I think he would provide a comparison chart or so to explain why it's worthwhile to pay for products like this instead.


    You can find dozens if not more reviews on AV programs all of them will vary on who and why they think one is better than another. If you want to believe Avast free is the top choice based on your experience you can find a review to tell you that. Tomsguide is just that a guide based on things they feel are important. Pay programs come with many more features! If you feel you don't need or want these features then without a doubt they are not a good choice for you. What I want and need in a AV is very specific and might not be suitable for you. Same for most people there is no ONE SIZE fits all. It does not make them dishonest or biased just makes them have their own opinion no more or less. I come to this site for their opinion for a good reason I respect there opinions whether I agree with them or not.
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  • jraju1954
    Hi, I think that most of the av app for android is always running type taking phone battery resources. Is there a demand type scan antivirus prog for android in free version. Would someone say. i tried avast, it gives protection, but i do not know whether it has a demand type run of program. It does not have a user control install of its acessory software . Anybody knows
    0
  • tizziocaio
    Anonymous said:
    Fwiw, dealing with an issue now, of virus and/or malware, and after running bitdefender and it clearing what it found, I ran malwarebytes and it found over 10 more instances of malware. So though one shouldn't run live more than one at a time, I recommend having malwarebytes and run it periodically, too.


    bitdefender dont like it because forces to make an account and sign in before using it..like "meh rly?"
    Also does way to often background scans and updates like 10 times every day...
    0
  • boma23
    I was running a repair and IT solutions shop a few years back. We regularly installed a free solution on MACs that came in, ahnd a busy week might see 5 - 8 Macs in the shop at once. Sophos free (which is what we used at the time) probably found nasties on around 60% of Macs that came in without protection. Make of that what you will, if you are in the "AV for mac is pointless" camp.
    0
  • Thomas_223
    Sophos auto-update is the worst. Hangs your computer until it completes. No way to stop it or schedule it. Kills productivity until it hopefully finishes or fails and you have to try again.
    0
  • Nickynike
    AVG is a very good freebie. It finds viruses and scans emails. Yet, no mention. Then I scan with Malwarebytes, again free.
    0
  • dusty13
    so microsoft did not pay there way into getting the definitions from the independent security institutes it seems ... because no one heard about av-studios "optimizing" their results in these tests ... ever ...
    0
  • Sue_21
    I have always used trend micro and I noticed they are not there. and it is really getting pricey $268 for virus. so i am looking for one that is not as expensive but as good
    any recommendations please
    0
  • Chris_361
    I agree that Kaspersky is far and away the best and nowadays uses the least resources . I don't know how they did it but it's amazing.
    0
  • Sreekanth_3
    Hi, I installed Norton Mobile AV on my Samsung S6 with Android 6.0.1 , but it's not helping with what I really wanted, which is to prevent my Chrome browser from being occasionally directed to random annoying sites. For example, one which says you have a virus, or one which says you won a prize. They don't do any damage, and I just ignore them and reopen the page I want, but it's the principle of the thing. How do I remove whatever malware is doing this? Thanks
    0