Best Free Antivirus Software

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To begin with let me say this: there is no best antivirus out there. Why do I say this? Any product that you take will behave differently against various virus samples since the AV engines and other components incorporated in them are of different technologies.

While one product might have higher detection ratio, another might have better malicious URL blocking or virtualization techniques, yet another might have lesser impact on system performance and so on.

Read more about Antivirus Engine and other related details at the end of this article.


Rated Products

Kaspersky Free Antivirus/ Kaspersky Security Cloud  

The paid security giant forays into free category and outsmarts its rivals

Our Rating: 
License: Free (Limited features)
  • Similar signatures & cloud features as its paid counterparts
  • Performance impact is decent on higher end systems
  • Strong behavioral blocker
  • Attractive GUI with no ads
  • Top-notch detection and always up-to-date
  • Thorough malware removal and disinfection process
  • Privacy policy (complies with GDPR)
  • Default settings cover most users
  • Bundles with Kaspersky VPN (can be uninstalled)
  • Fairly good web protection
  • Powerful exclusion settings (even for specific modules)
  • Extensive scan logs
  • Protection settings are locked with presets in Kaspersky Free Antivirus (KFA) [is available in Kaspersky Security Cloud]
  • Long but thorough system scans
  • Performance hit becomes worse on lower end systems
  • Slow update installation
Read full review...

Avast Free Antivirus  

The only antivirus with a fully customizable installer and selection of user preference components.

Our Rating: 
License: Free (Limited features)
  • Extremely light on the system with a modern and clean UI
  • The only antivirus with a fully customizable installer, selection of user preference components
  • Works best in hardened or lock-down mode, which blocks all unknown programs (medium-expert users only)
  • Top notch detection capability, many secondary components to offer variety to a wholesome software
  • Excellent malicious URL blocking, network protection, outdated software checking, integrated password manager, and comes with a rescue disk.
  • Deep screen technology that includes Sandbox and Safe machine components for protection
  • Bloated default setup, some ads and pop'ups
  • Account creation for further protection after a month
  • Lack of an anti-ransomware module, and Deepscreen disabled by default
  • Cloud reputation, Malware signatures and HIPS module needs improvement
  • Offers Google Chrome and various bloated secondary components during install [Choose custom install]
Read full review...

Comodo Internet Security Premium  

Provides a multi-layered protection scheme with HIPS, sandbox, antivirus and firewall.

Our Rating: 
License: Free (Limited features)
  • Feature-rich with lots of options for customization along with setting tolerance against prompts
  • Tweaked settings gives the best 0-day protection among the pack
  • Multi-layered protection scheme with HIPS, Sandbox, Antivirus and Firewall
  • Industry grade firewall with options for learning and behavioural blocker
  • Low on resources with various graphical skins available and a clean user interface
  • Painful for beginners to use it, not very newbie friendly 
  • Av-module is a bit weak especially the signature based detection
  • Auto-sandboxing happens for various legitimate files, troubles with FPS games
  • Too many tweaks needed for better protection
  • Buggy software and updates are released slow.
  • Chromodo browser, Yahoo search engine, custom DNS and Geek Buddy offered during default install. [Click customize installation during install]
Read full review...

Qihoo 360 Total Security  

This free antivirus is better than most commercial ones.

Our Rating: 
License: Free
  • Totally free, light on resources, extremely fast scan times and pre-configuration protection modes
  • Smooth running installer with no adware, pleasing UI and comes with many themes
  • Fast updates/fixes and excellent customer service with immediate replies
  • Great signatures with multiple engines and in-house cloud protection
  • Web protection addon, browsing locking, webcam, sandbox and usb protection modules
  • Online shopping protection, malicious URL protection and network threat blocking
  • Includes Glasswire Firewall and Windows patch-up components
  • Great detection rates, with very high zero day protection
  • Speedup and clean-up tools might not be for everyone (not present in Essentials version)
  • Bitdefender or Avira engines not enabled by default
  • Might encounter few false positives
  • PUP [Potentially Unwanted Programs] detection needs to improve
Read full review...

Avira Free Antivirus  

A free antivirus with high quality signatures, very fast updates and less false positives.

Our Rating: 
License: Free (Private/Educational use)
  • Pretty light on the system and runs smooth without system slow-downs
  • Clean ad-free GUI, Ad-free installer, No pop-ups or ads
  • High quality signatures, very fast updates, excellent detection on non-zero day threats
  • Deep file scans with very less false positives
  • Avira Protection Cloud makes for an excellent cloud engine
  • Browser safety Add-ons available for major browsers
  • Zero day protection (heuristic & behavioural shield) is very weak. 
  • Ineffective Browser launcher which is a memory hog (can be uninstalled)
  • Painful removal for detected files. Repeated scans from Luke Filewalker increases CPU & RAM usage. 
  • Multiple file exceptions needs to be added (real-time and on-demand)
  • No firewall/sandboxing/web shield technologies
Read full review...

Panda Free Antivirus  

Gives you antivirus protection with low memory and CPU usage, and collective intelligence cloud security.

Our Rating: 
License: Free (Private/Educational use)
  • Low memory & CPU usage thanks to cloud protection
  • Tiled UI with customizable interface and nicely rendered Settings interface
  • Collective intelligence cloud security - Downloading virus definitions is history
  • Good detection rates and behavioural analysis program
  • Fairly good web protection and hardware resource handling
  • Dependant on internet connection leading to weaker offline protection
  • Slow scanning speed, no fingerprinting (successive re-testing same files) and at times issues with virus removal
  • Not really light, performance impact in web browsing, installation and copying
  • Certain false positives despite the information available at cloud
  • Watch out for Panda security toolbar during install
Read full review...

Honorable Mention


Related Products and Links

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Antivirus Engine

It is used for Real Time malware protection of files and is the core component to scan data on your PC for detecting and removing malware from hard disk, memory, boot sectors, network drives, removable disks, or from external network traffic (internet).

  • How does an antivirus detect malware:

Firstly you got the signature-based detection which contains an offline database of known patterns of malware downloaded from the internet which can identify specific malware codes or family of malware. Then you have heuristic based detection that identifies pieces of code that are unlikely to be found in legitimate programs and hence is prone to false positives depending on the sensitivity of heuristics. Virtualization and sandboxing unpacks or executes unknown programs in an isolated secure environment so that their behaviour can be analysed and scanned using the antivirus engine. The latest one is cloud based detection that requires a reliable internet connection and sends the suspicious scanned file over the internet and the analysis is done by the vendors' machine running the cloud engine.

  • Scanning for viruses:

Most antiviruses include these basic scan types: On-demand scan/manual scan is initiated by the user from right click context menu or from within the software. On-access scan is initiated when the resource is being accessed like running an executable, copying files from external drives etc. Scheduled scan periodically ensures that the system is free from malware by setting the time and frequency for scanning. Startup scan/quick scan checks most important locations like running processes, startup items, system memory and services, boot sectors and so on.

To be Continued in the next update....... Firewall, Proactive protection, Web protection components and more.



This software category is maintained by volunteer editor George.J. Registered members can contact the editor with any comments or questions they might have by clicking here.

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Please rate this article: 

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Average: 4.3 (2216 votes)


Thank you.
Thank you.
New antivirus. SkyShield Antivirus:

I would not install Sky Shiled on my PCs. Why?

- New company / site since Feb 2014 according to Netcraft.

- Zero information on their website about who the company is and where they are located.

- zero reviews other than those placed by the company or its supporters.

Enough said, period.

I like the way the "Learn more" button just scrolls you further down the same page with absolutely no other information about the product or where it comes from (unless I'm missing something?) :D MC - Site Manager.
Well, information about the product is there, but not about where it comes from, or anything else regarding that matter. I didn't notice that... thanks for bringing this up. Caution needs to be exercised then, or maybe wait before more information about this product comes around.
I certainly would not install this (at the moment) into anything I had not already consigned to the bin for other reasons. :D Could not find anything for it either over at Wilders which is usually the first place stuff like this appears. There is a "review" for it at Softpedia which states: "It’s an appropriate solution if you just need a self-sustaining antivirus that does its job but on the other hand, if you might want to schedule a scan, grant permissions to certain apps or even view the quarantine, then you need to look for another antivirus. All-in-all, SkyShield Antivirus might not be all that buffed up with features and well, it’s not that versatile, but it is a straightforward and user-friendly solution that can fit well on any system". .... and then goes on to give it an almost 5 star rating for reasons I've yet to work out. :)
I agree with you. I just saw the antivirus on one of the download sites, and just thought to share. I didn't give much thought on it. Should have :D. It's fairly new though, so it might turn up on Wilders soon enough, as more people catch up on it.
I'll see about adding it to my article about How to Report Malware or False Positives to Multiple Antivirus Vendors: but from what is available about this product it seems to be a far cry from any AV which I could consider recommending. Perhaps that will change in the future. Thanks for pointing it out though. It's always good to see new players entering the field. I'll keep an eye on it.
I had a quick look today at 360 Total Security which is the new product replacing 360 Internet Security "in the near future". I activated and updated the additional engines OK, including Avira, but on running the program, no notifications for scanned downloads or indicators as promised when entering a shopping site, despite all of this being configured in the settings. Can't find any info about which browsers are supported (or not) but I tried using IE11, Chromium and Pale Moon. Guess I'll come back to this once it's had a bit more time to mature. MC - Site Manager.

Quick basic help question concerning AVAST: I've been using AVAST free, the trial period is up, can I continue it as is, and will I have adequate protection? Will I now need to manually update and/or run it?

Thanks, George in Tallahassee

If you use Avast free, you have to register for it, which is free. You can find the registration under Settings. When you register, the program can be used without any problems for an year. After an year, you can again register it. Or, if you reinstall Avast anytime again, you can register it again. Registration is free, so no problem.


It has come to my attention that AVG will not detect any part of Opencandy as malicious. AVG and Opencandy now have a deal that AVG not detect opencandy as malicious. That offends me !! If that is truly the case, then AVG does not deserve to be on your list !! For this reason, I personally will never put AVG on my computer ever again !!

If you, or anyone else, can provide a link which shows this I will look into it. However, the most I would do is put a disclaimer as the program would still be effective at protecting users from truly dangerous malware. That said, I will need to see a link before any action can be taken. Thank you for bringing this to my attention.


I read what I wrote in a Magazine. I do not remember the name of that magazine off the top of my head. I am going to do my best to find the proof of what I wrote here today. I will be back in touch when I acquire that information.

Thanks for your response

None of us here, and I guess most outside, do not like OpenCandy or how it operates, but it is not malicious as indicated in our information page about it here. We also need to remember that unless as individuals we never search for deals and have completely opted out of the consumer society we helped to create, then we are all responsible for OpenCandy's existence. The bottom line though is there are plenty of OpenCandy free alternatives for most software categories, and the offers it generates are easily avoidable if care is taken during the install process. MC - Site Manager.


I agree with everything you said 99% !! But what I have a problem with is that an antivirus program creator can be paid not to detect one thing or the other. That is a big problem !!
As far as Opencandy not being malicious, that is a matter of what your definition of what malicious is. My definition of malicious defines Opencandy as malicious. But that is not an arguable point. Just a matter of opinion. I think you could put a disclaimer with AVG that it does not detect Opencandy. Thank you for your response!! You will hear no more from me on this matter !!

Please provide links to substantiate your claims about AVG being paid not to detect OpenCandy otherwise you risk the inevitable conclusion that your posts are just trolling. MC - Site Manager.

I can not find that magazine article. I will keep looking.


I have no link to give you. I read it in a Magazine, and I do not remember off the top of my head what the name of that magazine was. It is not my intention to be trolling, Please feel free to delete my comments. If I find that magazine in the future, then I will be back to give you that info. Have a GREAT DAY sir !!

Not many AV scanners do detect OC inside installers.

For instance the FreeFileSync installer, which runs the Open Candy exec OCSetupHlp.dll, is passed by most of the major AV providers. Malwarebytes flags it as a PUP.


I clicked on your link, and if virus total is saying that Bitdefender does not detect OpenCandy, then that is just wrong! I had to update PDF Foxit Reader yesterday, and it comes with OpenCandy. My Bitdefender Free Edition did detect OpenCandy yesterday !! Then I proceeded to remove it from my system.


If you read my comments all the way through, then you will see that I have a bigger problem than just with AVG not detecting OpenCandy. I think that all the antiviruses in this list do detect OpenCandy in one form or the other.I am sure there are several out there that do not detect OpenCandy at all. In my opinion that is a mistake. At least detect it as a PUP.

Thank you for your response !!


So far i used and recommends/install Comodo Internet Security to my neighborhood. Though comodo antivirus never had a chance to be in any top 10 best antivirus reviews in my experience my system is stable so far and can be commercially used that does not required activation. My downside is i never used my pc like i dont care..?! Like i dont go to any site that has bad ratings on it or i feel that a site is a bad site or a link is a bad link - I dont download and open any file which is unknown to me. Bad thing is that few people does that. It was confirmed to me when i recommends it to a company and they installed it to hundreds of computers - they say most of their users dont really care what they click because they know someone will fix it.

I wanted to tried avast and bitdefender but it does required registration and activation - and it is a bad thing for offline users. They should remove registration and activation. And should be a standard for any free software.

Thank you for your feedback. My problem with most of the antivirus reviews is that they tend to put most of the emphasis, in one way or another, on detection of threats. However, I am of the opinion that for a user in the real world what really matters is whether the computer was protected from infection or not, regardless of how it was protected. As for Avast and Bitdefender, I do understand what you mean about activation. However, hopefully there is a way you can connect your computer to the internet for the small time required for activation. Still, I agree it would be best if they could keep track of users in some other, less intrusive, manner. Let me know if you have any other questions. Thank you.


I have looked through you sources as follows :



Dennis Technology Labs

What I found was, is that Comodo Antivirus was not presented as a stand alone product, but as a suite. I only found three from your list of antiviruses, that presented their antivirus as a stand alone product. As per this link :

I have seen testing of antivirus programs, that tested much better within a suite, than as a stand alone product. Do you have any test results of Comodo Antivirus as a stand alone product?

Otherwise I will have to go with one of the other three that were tested as a stand alone product. At this point, I do not see how Comodo Antivirus stands as the best, when I can not find their Antivirus, tested as a stand alone product.

For the record Comodo Internet Security Premium is also freeware.

George J,

Thank you for your reply.
I am aware of that.
Thanks !!

I should clarify this in the article as well, and I will during my next rewrite. I can use the results for CIS because the core protection, at least against any malware which makes its way onto the system, is identical between the two products. If there does become a difference then I will no longer consider the results for CIS to be comparable to Comodo Antivirus. I hope that makes sense. If you have any questions, or do not agree that the protection against malware on the system should be considered identical, please feel free to ask. Thanks.