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  • Excellent malicious URL blocking, network protection, outdated software checking, integrated password manager, and comes with a rescue disk.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...

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...

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...

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: 

Your rating: None
Average: 4.3 (2219 votes)


Okay, after 2 1/2 hours of struggling with Avira I never could get web protection to work. So I went back to Avast. But now they charge for features I used to get for free... I mean I got those features 3 hours ago and now they want to charge.

Oh yeah, and they installed Google Chrome again without even telling me they would much less giving me a choice!

So maybe I'll just have to pay for protection (though until a few hours ago I got the best I ever had for free . . except for the Chrome thing). But you can bet I will NOT get Avast. [Commercial reference removed]

But it really stinks that the guys I used to trust are trying to stick it to me now. I guess Google bought them so the good times are gone.

There are clear checkboxes on the installation window to opt-out of Google Chrome, if you don't want it installed on your system. In case you update Avast via its internal updater to a new version, then too, after updating, a window pops up where you can opt-out of Google Chrome. Maybe you missed those? Avast has a free version, since long time, and it continues to have it. So, again, maybe you downloaded the wrong setup file? Avast still remains an excellent choice amongst free antivirus.

Might Lavasoft's Ad-Aware Free Antivirus + 11 be placed in the queue for future consideration?

They have replaced their Viper-based scanning engine with one from Bitdefender, and v.11 has garnered a positive review from CNET's Editor (and several users) -- .




I just went through a miserable week with Ad-Aware...

I downloaded V10.5 a week ago Friday, installation went well, light on resources, didn't seem to slow down any application.

On Monday, V11 was released and things went down hill from there.

It was a mess.

On Wednesday they released another version, not an update, but another version.

I had all kinds of issues, I had to start monitoring manually, the tray, a separate .exe file, would never initialize, nothing would work.

I went to the forum, they had me delete services and other components they said were from Version 9 (how could this be, because I never installed anything from Lavasoft before V10.5).

This was supposed to be the root cause of the problems.

After I deleted what they said was a "service" from V9, nothing ever worked again - I couldn't get it to even manually start.

I also don't like the idea of having their browser protection software included, frankly I never understood if it was initialized or not. I know the toolbar was not installed, but as for the software running, I don't know.

It was listed as a separately installed program in both Windows Ad/Remove and in Geek's removal program, and even after I uninstalled Ad-Aware, I had to remove the Browser Protection separately.

I am not going to reinstall it.


Thanks for taking the time to detail your experience with Ad-Aware Free A/V+ 11; I'm sorry to hear that it was so miserable (it appears that Ad-Aware Free Antivirus+ 11.0.4516.0 is the current version, released on 2013.10.09).

That version 11 currently garners an overall user rating of 4/5 stars (from 29 reviews) at CNET, perhaps your difficulties were in some way related to your particular system and configuration (another positive review was posted by Thetechhacker --

In any case, it will be interesting to see both what additional formal tests reveal and other users' experiences over time are (to be fair, I have not experimented with it yet).

Take care.



Thanks for that AJ, I'll definitely take that into consideration.

Hello JT,

There's one other free application I've recently read about that may be worth a look when you've the time, CYSEC Free Anti-Virus, which garnered a very positive review from the UK publication Security Magazine -- .



No information at all about how CYSEC was tested, and against what. Unlike Avast! and AVG however, it has no web protection or email security so in the real world it will be practically useless. It also requires the user to download a separate installer every time they want to do a full system scan. IMO users will be better off with one of the more complete products listed in the review above and using VirusTotal for secondary opinions. MC - Site Manager.

Thanks, MC.

Thanks for an excellent site,am currently testing 360 internet security,seems very good and light on the system,run this with malwarebytes free and windows firewall,comodo dns server,privdog and wot,Firefox.

too many false positives will,go back to Panda cloud av

After reading several positive reviews of Microsoft Security Essentials, I decided to give it a shot thinking that my PC would be well protected.

I then came across this article today which I think should be shared will the readers of this forum who believed in MSE. After reading it, I quickly removed the product and switched to Avira Free for now which no longer has the nag screen.

Since there is now so much controversy, imagined or real concerning MSE and its effectiveness, I think Gizmo should remove MSE as a recommended product until we learn more.

Presumably you did not read the other comments below? This is just another attempt to slag off MSE by taking what Microsoft actually "said" out of context. In fact this is just copied verbatim from PC Pro as indicated at the bottom of their article. There is nothing more to learn from this other than Microsoft are being more honest about the capabilities of a single security product than other vendors. They already explained their strategy here. False positives also remain an issue with other products, this being just one recent example. You will also find plenty of reported infections by users of every antivirus product, including Avira. :) MC - Site Manager.

If you like MSE, then stick with it. It is just a matter of opinion.

I did read the comments, and the person to who you refer in your quote is different than the one in the quote I mentioned.

Regardless, if Microsoft Programming or Software Managers cannot get their stories straight, they both seem contradictory to me, I would rather deal with a product that is more proven and established as effective.

IMO this is prime example of how the media are able to manipulate readers into believing something that isn't true. The quotes from Microsoft in the article you referred to are no different (of course) from the source they were copied from. The fact remains that no one security product will protect users from everything no matter if the vendor calls it "360", "Total" or anything else that sounds like it will. Member cybersun comments below that he has used MSE for three years without any issues, and yet was considering changing on the strength of this article. This is what these folks want you to do of course because the revenue they generate does not come from MSE but from the advertising and so called "offers" they promote for paid antivirus. This is just tabloid journalism come to tech media. Maybe the author used to work for the Sunday Sport. :D MC - Site Manager.

"The fact remains that no one security product will protect users from everything no matter if the vendor calls it "360", "Total" or anything else that sounds like it will."

I'm a little confused now. I was wondering which one would be better, Bitdefender or Avast 2014. Do you think both are so good as each other?

Both are very different in that Avast! is a full on application whereas Bitdefender adopts a more minimalistic approach. In this respect the configuration options are limited which might not suit users wanting to have total control of their security configuration. The detection power of Bitdefender however is top notch so overall the protection performance will be very similar. Both program though will need some supplementary assistance to achieve optimum system protection. See the link below for some suggestions. MC - Site Manager.

Thanks, MC. I checked that page. Very informative! It helps me a lot.

If you look closely at the articles, these are not examples of media manipulating readers but contradictory quotes by Microsoft's own people. That being said, Microsoft should be making one consistant statement across the board regardless of test results or efficacy debates.

If a company cannot, will, or appears not, to stand behind their security product, then I personally am not comfortable using it.

Like I intimated earlier, useage boils down to personal preference.

Listen, I am a bit surprised to read your review. I just ended up reading an article in HOW TO GEEK where they specifically say that even MS recommends now to use 3rd party AV, as their MSE now ranks last in the list of FREE AV Software. Isn't that info available to you also? In fact all agree in saying that AVAST is the best Free AV but has a loaded interface... I would be thankful to read any comments by knowledgeable individuals on this topic. I have trusted MSE for over 3 years now, I haven't had any issues, but reports such as the one in HOW TO GEEKS (yesterday newsletter) worries me. Of course MS reputation for their blunders help in not feeling to safe about MSE or its future in fact.

This website and others are taking what Microsoft actually "said" out of context. Most of what was "said" relates to the ability of MSE to pass tests which is what they and other vendors spent a lot of resources on previously. In yours and my real world, these tests are as irrelevant to antivirus programs as Matousec is to firewalls. You could of course keep a log of your internet and other computer activity activity, spend 6 hours a day comparing this with what your antivirus "fails" on in various tests, find one that matches and say Oh yeah, I went to this site on 19th July so maybe I was at risk. This of course is impossible and would also be a ludicrous exercise, even if it was. What Microsoft did say was this: "It’s not as efficient to have one kind of weapon. "Like anything you must have that diversity. It’s a weakness to just have one." This is what we here have been saying ever since the site was set up. Multiple layers are necessary in order to provide optimum protection including browser extensions, a DNS filter and the adoption of safe surfing practices. No one single product can achieve this on it's own although many vendors claim to. This is described in more detail here: The bottom line is, if you have been using MSE for three years and not been infected, why now should you suddenly be at risk? MC - Site Manager.

Windows Security Essentials does not run on Win8. Windows Defender runs by default and now includes virus detection.

A good review of Defender and other Win8 protections can be found here:
However, they too state that "Microsoft has said that Defender on Windows 8 provides an 'acceptable minimum level of protection', and that it will disable itself automatically if another antivirus suite is installed"
Maybe MS is just being honest. :)

The main reason it'll disable itself automatically is to avoid conflicts that may arise from multiple AV's running at the same time. Worst case scenario would be system crashes and so on.

You should be careful not to confuse MICROSOFT Security Essentials with WINDOWS Security Essentials. Believe it or not, there are some questionable sites offering the latter, e.g.

Rogue antivirus programs have been known to take advantage of people who are careless about the exact name of a program.

My Bad, Joe. Seems I can't edit that anymore to change to MS.

"Microsoft has admitted Windows users should install antivirus above and beyond its own Security Essentials, describing its protection as merely a "baseline" that will "always be on the bottom" of antivirus software rankings."

So, how about replacing MSE with Qihoo or Comodo antivirus?

Please supply the quote from Microsoft stating this and not the interpretation of their meaning from a media publication that obtains revenue from commercial security software. In fact no such quote exists from Microsoft and if users read the whole article they will obtain a more balanced view, including that related to tests. This is just another example of the 'mine is better than yours' scenario whereas ever since malware first appeared no single application could guarantee to protect against 100% of it unless additional measures were taken "above and beyond" its own capabilities. Of course the vendors of commercial products continue to claim this because they want users to buy their software instead of using free solutions. In this respect, MSE will always have a place in this review. Thousands around the world use MSE without getting infected and I still receive emails from owners of top commercial programs that have failed to do so. In summary, PC security does not revolve around the installation of one single product and thereafter being safe. If users employ MSE as their "baseline" solution and then adopt the same measures necessary to compliment other products, then the resulting level of safety will be the same.

I just quoted what the website said. I have no problem if Gizmo's freeware review MSE. I too have good experience with it regarding protection. Specially zero false positive. But I had some performance issues on two different computers while using it though.

I too experienced very high intermittent CPU with one installation and was never able to effect a permanent cure. This was quite some time ago now though so maybe this is no longer an issue. MC - Site Manager.