Free Antivirus Comparison

This posting will discuss which of the following three programs deserves the title of “best freeware antivirus program”: Avira Antivir, Avast, or AVG. My conclusion: all three are very worthy contenders that can hold their own or surpass any heavyweight for-pay antivirus; however Anitvir and Avast are definitely in the first tier, while AVG is a close second tier.

There’s been a vigorous debate going on in the little “cbox” message box (in the sidebar) over which freeware antivirus program is best. This posting will explore this issue more closely. The objective is to go beyond the ubiquitous “I have used program x for y years now and it has kept me completely virus free” to a more substantial comparison.

The findings presented here are not my original work but come from a single source: AV-comparative.org’s antivirus comparison tests conduced in Nov 2008 (test #20) and Feb 2009 (test #21), which are the latest as of this writing. It is somewhat difficult to reference these as sources because the av-comparatives site disallows direct linking to the test results and requests that all links be to its root domain (presumably because new tests are always published and they do not want links to results that may be obsolete).


The choice of programs: Antivir, Avast and AVG are the most used and most well known freeware antivirus programs, and I use or have used all three for long periods of time. They are also most likely the top three best freeware antivirus programs. The reason I am not expanding this discussion to other programs is because it is much easier to limit the scope to software tested in AV-comparative.org’s tests, where there are hard numbers to back up any claims. Having said that I would have personally liked the addition of at least two more: Comodo Antivirus and Rising Antivirus (both of which have a lot of fans).

By way of comparison and to provide some perspective I will also include some of the numbers for two of the best paid antivirus programs: Kaspersky and ESET NOD32.


Summary of findings: Antivir and Avast and both have excellent and comparable detection rates. Not only are these on par with the best commercial program, Antivir in fact has the best detection of any program free or paid according to AV-comparatives.org’s numbers. AVG, however, lags behind the other two somewhat in that area (although it is still by all means an excellent program). Antivir has what seems to be a significant advantage in terms of predictive, behavioral-based “heuristic” detection (for brand new threats that are so new they have not yet been added to the antivirus program’s database).

Where AVG has a good advantage is in the number of false positives (lower than both Antivir and Avast, both of which exhibit comparable numbers of false positives). However, AVG scores another strike against it in terms of its scanning speed, which is significantly slower than the other two.

The freeware version of Antivir displays an advertisement on every update, which is rather undesirable; however, this can be easily disabled (look here, here, or here). It also “does not support email scanning”; however, this is also a non-issue in my opinion, a red-herring designed to scare less tech-savvy users into purchasing the paid version. The reason I say this is a non-issue is because although Antivir may not scan your email for virus as it downloads, it will still protect you from it afterwards, not just during normal scans as it will also intercept it once it is on-disk and/or if and when it tries to act up.  In fact email scanning as such may be completely redundant and a waste of time; see this article for more info.

Antivir is my favorite freeware antivirus. It is best in terms of performance and, with the recent addition of an antispyware component it has become even more desirable. However, if asked to recommend a freeware antivirus Antivir comes with too many caveats and explanations (the nag screen, the email scanning (non)issue). It is easier to recommend Avast, as it provides comparable protection and performance, and is an excellent product.

AVG is my third choice. It also provides excellent protection and has the edge with respect to the least number of false positives, but its performance and detection rates lag behind the other two.


The numbers (and other issues considered):

  1. Detection Rate / on-demand scans
  2. Detecton Rate / predictive “heuristic” detection
  3. Number of false positives
  4. On-demand scanning speed
  5. Versions tested
  6. Links and downloads


1. Detection Rate / on-demand scans: this data comes from AV-comparative.org’s Feb 2009 test (#21). The programs tested were subjected to 1,274,928 instances of malicious code collected between Apr 04-Apr 08. The reason: any malware collected prior to this is considered fairly well known by now

  • Avira Antivir: 99.7% detection rate
  • Avast: 98.2%
  • AVG: 93.0%
  • Kaspersky (*): 97.1%
  • ESET NOD32 (*): 97.6%

* Note: no free version of these offered. They are listed here to give ’perspective’.

The data seems to show that overall the detection rates are very similar (the differences are unlikely to be meaningful), with the exception of AVG which has a somewhat lower rate of detection than the others.


2. Detection Rate / predictive “heuristic” detection: this measures the program’s ability to detect new threats (based on their behavior), before they becomes known and are included in the program’s updates. The data in this section comes from AV-comparative.org’s NOV 2008 test (#20). The programs tested were subjected to 45,831 “new” instances of malicious code collected between Aug 4th-31st 2008 (4 weeks in total).

  • Avira Antivir: 71% (over 1 week), 67% (over 4 weeks)
  • Avast: 40% (over 1 week), 39% (over 4 weeks)
  • AVG: 43% (over 1 week), 40% (over 4 weeks)
  • Kaspersky(*): 71% (over 1 week), 60% (over 4 weeks)
  • ESET NOD32(*): 54% (over 1 week), 51% (over 4 weeks)

The results above seem to show that when handling yet unknown threats (malicious code that is so brand new that it has not been added to the program’s database), Antivir and Kaspersky have an advantage over the others.


3. Number of false positives : false positives can be as much of a problem (or even more) than undetected malware, in that deleting innocent files can cause unpredictable errors and problems. This data comes from AV-comparative.org’s Feb 2009 test (#21).

  • Avira Antivir: 24
  • Avast: 28
  • AVG: 17
  • Kaspersky (*): 14
  • ESET NOD32 (*): 13

Interestingly, Avast and Antivir have significantly higher false positives than the two paid programs, with AVG having the lowest number of false positives of all three freeware antivirus programs.


4. On demand scanning speed : this data comes from AV-comparative.org’s Feb 2009 test (#21). The throughput rate is in MB/sec.

  • Avira Antivir: 13.6 MB/sec
  • Avast: 15.4 MB/sec
  • AVG: 6.8 MB/sec
  • Kaspersky (*): 13.3 MB/sec
  • ESET NOD32 (*): 13.2 MB/sec

On this metric AVG significantly lags behind the others, who are otherwise very similar, with Avast having a slight overall advantage.


5. Versions tested: note that the versions tested were the paid versions. I am assuming that the basic engine is the same in the free version as well, and that the results apply there. For Antivir, the freeware version is different in that it does not perform email scanning and displays a nag screen, but these have already been addressed above. Also, as of this writing the newer version of Antivir includes an antispyware component.

  • Avira Antivir: 8.2.0.374 (test 21), 8.1.0.362 (test 20)
  • Avast: 4.8.1335 (test 21), 4.8.1229 (test 20)
  • AVG: 8.0.234 (test 21),  8.0.156 (test 20)
  • Kaspersky (*): 8.0.0.506a (test 21), 8.0.0.454 (test 20)
  • ESET NOD32 (*): 3.0.684.0 (test 21), 3.0.669.0 (test 20)

6. Links and downloads: go to the respective program pages to download the latest version. Note that the freeware versions are for single computer home use. License(s) required for commercial use.

Related Posts with Thumbnails
Please share this page:
  • Digg
  • del.icio.us
  • Facebook
  • StumbleUpon
  • Twitter
'

103 Responses to “The best free antivirus: a comparison”

  1. Taurus says:

    Soo…it comes down to Avira and Avast? I’m clueless, ’cause I have to put a little haste in my search for free antivir. before my McAfee sub ends (which isn’t fair)..
    I’m just looking for something that scans EMAILS TOO AND IS FAST AND LIGHT & RELIABLE..hope you folks can help me. Cheers,

  2. W4L4CH1 says:

    Yupzs it’s been a long time I’m still trust and using avast antivirus. For you Taurus… Avast can do what you want for you.

  3. Rich in Ky says:

    I pay for NOD32 …..simply wonderful….never any problems….and it updates without a hitch ( and often …..don’t think this was mentioned much in the reviews )

  4. Jim says:

    The big flaw in Avast is the terrible amount of memory and resources it hogs as you surf.

  5. hanum says:

    nice comparison review. Thank’s a lot ^_^

  6. diwas says:

    kaspersky the best of bests

  7. Bjorn says:

    Avira is exceptional in the fact that it crashes during boot sector scan (other tests work properly). And it seems that I am not the only one experiencing that issue. There are half year old reports of the problem on their site without solution. Some users report that bug seems to be introduced in version 9, as the same feature was working OK in v.8.

    Going back to AVG.

    BTW, nice anti-vir comparison. Thanks!

    Take care,
    Bjorn

  8. Antivir says:

    Yep, Avira 4ever! I am using this product for years and i am satisfied…and Avast is also not bad!

  9. Shiw says:

    This comparison was very good!
    But I’ll prefer avast than avira because I think the free one don’t have antispyware!

  10. Prashant says:

    KASPERSKY is the best of all antivirus if it is updated………
    no other antivirus can cath it….?

  11. James Bond says:

    How about using a Mac?
    Linux has a promising comparison as well.
    Let’s see. 60,000 known viruses for Windows
    40 ((Not thousand but only 40)) for Linux
    Approximately 5 or 6 for a Mac.
    Why? Linux and Mac’s both use Unix as their back-end. Funny enough but ask Microsoft what they use as their top web servers and you might be surprised to find out that some of them are Unix.

    Let’s see what the counter from Microsoft is: Yes but Windows is more widely used and therefore has more eyes on it, therefore has more viruses. Ok that would make sense for maybe 50 more? Maybe 100 more?? but 60,000. I hope that settles the debate on which Anti-Virus product is the best. It’s like saying “Which Syphillus cream will work the best on me?” I think the best solution will be to avoid the viruses altogether, but that is just my opinion.

  12. don’t know why people mention AVG, It will no longer be Free post Dec!

  13. Windows says:

    Windows is the best OS EVER.
    That unix crap can suck a rock, everyone uses windows.
    Linux and Mac are for geek losers.

  14. Nosmiley says:

    I have tried all the top 4. I keep coming back to avira. I have had a paid subscription to Kaspersky for the past year, with a year left to go. I use free Avira instead. Kaspersky may be super high quality as advertised, but Ordinary People [ME] don’t know enough to program it to work up to its’ potential. Allowing the program to run in the default mode, it doesn’t catch as much as Avira. An ordinary Geek may be able to tweek it to work as its supposed to. It has all sorts of ways to change,add, or eliminate things,but clicking on these options, you’ll find if you’re honest with yourself, that you don’t understand the terms they are using, so you don’t know what you end up with.It’s nearly impossible to get rid of every bit of it,if you decide to uninstall.

  15. Rhys says:

    I have used AVG for years. Talking to many people, like my friend which is a gammer he thinks avast is the best because it don’t use a lot of resources and doesn’t effect your gameplay at all. Having said this I have never had a problem with AVG, but to be honest it is a bit hungy but it has always kept my computer free of viruses. I haven’t had much to do with any other scanners. I think they are all great programs and all do a good job. I don’t complain because they all can make a better one than I can. So doesn’t matter, find one that you like and stick with it!!! :)

  16. balakganesh says:

    Please check out Microsoft Security Essentials & rate it .

  17. Soumik says:

    I am Very happy with my Avira. I Think it is Best Free Antivirus…

  18. larry says:

    i have used avira for 2 years now but recently a virus just entered in my system. the virus is just like a bot, im using yahoo messenger then suddenly it sends a message that hardly understand and it automatically sends to every online in my list of friends. its crap. damn. help me pls

  19. simmhan says:

    why should anyone look for freebee antivirus software products while microsoft offers its own free antivirus ‘microsoft security essentials’.its hassle free and has a significant number of satisfied customers…check it out….

    http://www.microsoft.com/Security_Essentials/

  20. Carbonize says:

    @simmhan – That makes no sense. Why look for free anti virus products when MS offers a free anti virus product? How would anyone know about the MS anti virus unless they were looking for an anti virus?

    Also Microsoft Security Essentials is still a very basic product.

  21. Zulu warrior says:

    How many have heard about Vipre. There is one word to describe it. It leads, others follow. Speed, less resouces, user interface, available for free etc.

  22. Karim says:

    malware removal is also an important factor in deciding an anti virus tool. Detection is important but if your favorite tool can remove the malware with no adverse side effects that’s a winner. Else, what’s the point of detection.

  23. Joe Davis says:

    Not sure if I overlooked the mention of the PC World’s results which can be found here http://www.pcworld.com/reviews/product/290836/review/antivir_personal.html. This shows that AVG has fallen behind and that Cloud Antivirus may be the next rising star in antivirus protection. It also mentions the ability of Avira to detect viruses better heuristically. I like Avira and feel that it meets my needs. In the past it has performed better than paid for products that my family have had on their computers. Maybe in time I will move from Avira to Cloud, just as I have moved from AVG to Avira in the past. Change is inevitable and holding on to outdated virus protection seems silly, but like many I have an aversion to change. For now I will stick with Avira while keeping an eye on Cloud.

  24. Amir says:

    GDATA is the best,Do not waste youe time with other AntiVirus

  25. MihaiSL says:

    BitDefender has a free version, which is better than Avira Antivir, Avast, AVG. You can download BitDefender 10 Free Edition from their web site. BitDefender, Kasperski, F-Secure … are the best. Norton and McAfee obtain good results in some tests because they pay that labs.

  26. Scott says:

    I used to have AVG until they automatically reset my default browser to Yahoo, and crashed every time I switched it back. That kind of imposition has to be part of any comparison. Sometimes I wonder if the antivirus people spend too much time dealing with the darkside that a bit rubs off – the free Nortons can get pretty nasty too after the sample period runs out.

  27. Mark West says:

    I don’t think avira have a best detection and the best antivirus. I have used a avira and the detection for virus is so poor. I recommended you (A-Squared Free) it the best antivirus even the hidden virus can detect it.

  28. Cody says:

    Yeh AntiVira Is great on Its detections, to be honest I dont even think Avg can even have that high of a detection rate some of the multiple scans ive ran before and seen the difference in detection, God damn. But Had a strange possible Antivira false positive recently something with .Net Framework after a Hidden file was removed,it was real strange.

  29. FLiTz says:

    I’ll tell you, kaspersky is the best antivirus fi you wanna paid for it.

  30. - says:

    using avira or KIS on normal-use pcs
    after avira discontinued av for win9x, have used avast4 on win9x (sort of a hobby/interest keeping old pcs safe & usable),
    don’t know how long avast will provide definitoins for avast4.
    also wonder if kernelex can allow any of these free av to run on 9x.

  31. brousse.ouillisse says:

    Dear Samer,

    OMHO there is some inconsistency in your test:
    1/ if you want to review freeware antivirus, why did you test the paying version of Avira ???
    2/ Microsoft Security is also freeware and it would have been interesting to add it in your test
    3/ CPU and memory usage are also interesting criterias (though I admit that they should be considerated as secondary, as an antivirus is about security first)
    4/ it seems that as a conclusion of the iAWACS (International Alternative Workshop on Aggressive Computing and Security), no antivirus software can now advertise without being considerated as a fraud. French students with simple user Windows accounts were able to hack PCs with 6 different attacks. The best of all antivirus only stopped 2 out of 6 ! (all the major products were used). Yes, no admin rights, strong antivirus and PC always compromised !

    I am now getting paranoid: Who and what can we REALLY trust ?

  32. Samer says:

    @ Brousse,
    My article was based on research done by AVcomparatives. Their comparisons did not invlude MS Security essentials and therefore I couldn’t discuss that. The article assumes that Avira paid and free are based on the same engine, and then goes out to point out some of the differences.

    CPU and memory usage are very relevant criteria and I would love to add them to the post (this post is about due for an update anyway).
    I also agree that an antivirus program by itself is not sufficient protection. Ideally you would want to be running a good antispyware suppliment (which both Avira and Avast have added to thier AV programs, and I recommend Threatfire), as well as a good firewall app (although I think that that’s not a critical component, although many would disagree).

    Re-reading your comment I will say .. remind me not to let any French students near my computer ;) I guess when there’s a will there will always be a way.

  33. AVP says:

    AVG 9 is much more improved and is quicker in detection compared to earlier version.

    Just my 2 cents.

    Cheers,
    AVP

  34. John Shelton says:

    I would love to see a repeat of this test, but adding Microsoft Security Essentials so there are 4 free antiviruses in the test.

Leave a Reply

*


You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>

Recent Comments

  • saber: this is fantastic topic i will put it in my site here : ??????? ??????? | ????????? | ????? | ?????
  • Windows XP Driver: Thanks a lot for sharing this info. I would definitely check drivermax. Kudos for sharing!
  • Gokool: Wanted to share a great news, guys. This program works flawlessly with Windows 7 (Home Premium –...
  • Samer: If anyone thinks that unsubscribing from a free service makes any sense, I have some bad mortgages to sell...
  • John: I don’t think whoever wrote this article used the application in question to split the 600 mb file using...