Best Free BitTorrent Client

Since its inauspicious public appearance 10 years ago  bittorrent has become one of the major download formats. With good reason too: it's fast, equitable and efficient. If you haven't yet installed a Bittorrent client on your PC, you should as there are some great freeware clients available.   In Bittorrent the best clients are free.  (In fact, if a client costs money, it is most likely a scam).

If you are unaware of the bittorrent protocol, you may take a look at my article, What is Bittorrent, as well as the listings within Searching for Torrents and Finding Legal (and free) Torrents to see the massive amount of content available through bittorrent.

Testing

Anyone with knowledge of bittorrent knows that it is nearly impossible to have a testing procedure that is foolproof in measuring small differentials in speed among bittorrent clients.  This is due to the fact that your download speed depends on the upload of other active users and there is no control over their actions while testing.  However, I have been testing clients for this category for several years and am convinced that the better clients can be separated from the others.

For this round of testing, I used 9 torrents, 3 from large and healthy torrents where high speeds could be obtained, 3 from medium sized torrents and 3 from smaller torrents.  I was continually moving back and forth between the clients to verify the differentials in speeds. 

There definitely was a difference between the superior clients and the excellent clients listed below, as well as substantial differences from all of those and the inadequate clients not listed here. For instance on the large and healthy torrents, the superior clients consistently reached speeds over 1.5MBps, while the excellent clients consistently maxed out at 1MBps.  The inferior clients fell quite a bit below the 1MBps level.  On the medium and small torrents the superior and excellent clients fared pretty equal, with the inadequate clients performing significantly worse (percentage wise).

Testing was performed on both Windows 7 64bit and Windows XP SP3.

Ranking

For my last review I separated the bittorrent clients that has toolbars etc., to a listing below those that bittorrent clients that had a clean install.  This time, I have decided to rank the clients based upon their results on the speed testing, their features and their help resources. 

I will make note of those that have installs or other changes to your system that are not necessary for the proper function of the bittorrent client.   I will strongly suggest that if you choose a bittorrent client that has these unnecessary add ons, to not accept those changes or add ons.

Thanks to a comment from Luke, I have added some information on private tracker acceptance of these clients.  While the vast majority of bittorrent users utilize public sites, this information will be pertinent to some.

Superior Bittorrent Clients

Although these superior bittorrent clients are listed in order according to the ranking criteria above, I will point out that the differences as far as speed are so slight that in real life there would be no real difference.  Any one of these bittorrent clients will perform as good as can be and the choice usually comes down to which GUI suits your personal preference.

qBittorrent is once again my top pick in this review.  I was unaware of the existence of this client until it was suggested by IronPlatypus in the comments here a year ago.   This time around, it was almost dethroned until a new version came out as I finished my testing.  When I finished my re-testing qBittorrent soared back to the top placing first on seven of the nine test torrents.  I was amazed at how quickly qBittorrent got going on the torrents.  Also, many of the other clients would have speeds jump around, but qBittorrent ran at a stable speed level throughout the download.  I was even more impressed this time around with qBittorrent.  I should add a caveat that the version just prior did not fare too well and was pushed way down this listing.  However, the latest version is as good a bittorrent client as I have seen  qBittorrent was also stable and efficient in both operating systems tested.  Its RAM use was low and stable as was its CPU use.  It has all the features that an ordinary user would want and is unlikely to cause issues on any Windows system. Their built in search is a real plus.  It runs quick and has a good number of sites included at default.  I am usually not a big fan of built in searches, but since this allows you to visit the web page for the torrent and see comments/ratings there, I find this search usefu and the best among all the bittorrent clients.  (Thanks to xTobix for reminding me of how good the search is)  Plugins for additional sites are available.  A downside to this client is that it basically is a one person operation, which might affect growth and support.  The updates seem to be coming regularly, so the growth is not  an issue as of yet (in fact they seem to do more updates than the other clients).  Another negative is the lack of acceptance at private sites, though not for any fault of the client other than it not being widely used or known.  The Wiki and Documentation have improved, but still parts are out of date.  The situation at the forums has improved from my last review.  Also I requested a feature change at their bugs page (the feature was already in the client-doh!) and received a instant response from the developer.  qBittorrent is a clean install, no addons etc.  Our Guides

 Pros:  Low and stable RAM and CPU with all the necessary features.  Excellent performance on torrents.  Development still seems to be very active and responsive to users.  Clean install, no addons etc.

Cons:  Basically a one person operation, which could affect progress (though it has not as of now).   Support has improved, but still needs work.  Not accepted at many private trackers, although I am sure it would be if it were more well known.

µTorrent was the top pick for two years in a row, but last time it was demoted, mostly due to their inclusion of a malware ridden toolbar at default on install.  They have switched to the Bing toolbar (along with a home page and search page change).  These can easily, and should, be avoided during installation.  Their uTP protocol looked to be a big step forward for bittorrent, but really has not amounted to much at this time.  Their recent addition of Apps looks more promising that I originally thought.  However, it still has not grown all that much.  Still, this is an interesting development that may grow into something useful for users.   µTorrent was to be chosen Top Pick again until the newer qBittorrent came out and performed so excellently.  Still, with the excellent results on the test torrents, the fact that it is a stable and low resource using client, the vast amount of features packed into this tiny program and the excellent support provided by  µTorrent's FAQs, guides and forums this is a top flight bittorrent program.  µTorrent is by far and away the most popular bittorrent client.  Once you get past the install addon and change issues, this is an excellent client for all Windows users.  Wide acceptance at private sites.  Our Guides

Pros:  Excellent speeds on torrents, efficient and stable client with a large amount of features packed into a tiny package.  Excellent help resources.  Leader in the bittorrent field at the moment.   Wide acceptance at private trackers.

Cons:  Has had critical security alerts at Secunia. (though none on this version) Bing Toolbar install and search/home page change enabled at default on install. Unnecessary DNA program enabled at default and should be disabled in Options after install.   Also, an unnecessary "app" (changes from time to time) is offered during install (enabled at default).  Thanks to Gavin for pointing this out.  The toolbar, changes and app should all be rejected during install.

Tixati is a relatively new bittorrent client that entered this review for the first time two years ago.  Of course, it performed excellently on the test torrents (or it would not be here), but it is also an appealing client, with its varied GUIs and layout.  Tixati was very stable in both RAM and CPU on both of my systems.  While its use of those is slightly higher than µTorrent or BitTorrent, it is still very easy on system resources.  Tixati always seems to be in active development and the developers are receptive to users input.  Compared to µTorrent/BitTorrent, Tixati is a Mom and Pop operation, which many users will prefer, but some may be wary.  This is reflected in their promise never to include addons/changes such as seen in µTorrent/BitTorrent.  Their help facilities have grown and are kept up to date.  Their forums are responsive, but not at the level of µTorrent's, which has the best support forum.  It s performance on the test torrents was only sightly below µTorrent/BitTorrent and for all practical purposes it is equal to them.  their interface options will appeal to many users.  Their clean install will appeal to all.  Not accepted at many, if any, private sites and being closed source will not help it gain acceptance.  Our Guides

Pros:  Generally stable and efficient with a good variety of options.  Developers are active and responsive to user requests.  Attractive interface.  Good help resources.  Excellent performance on torrents.  No addons etc. during install.
Cons:   Help resource, though very good, could use some more.  Smaller operation, which you may or may not like.

Halite is a client that made it into the top client list two years ago and I had hoped this client would make its move to the top as it is the most efficient client of all I have tested and only needed some additional features to move up. Unfortunately, halite has not been updated in over a year and this gives me some reason for concern about its development.  I, and a significant minority of Windows users had some issues with this version previously and it is disappointing to see no new version in response.  I should point out that those issues disappeared for me during this testing.    While accepted at many private sites, not as many as µTorrent or Deluge.  Their help facilities are limited as there are no guides or documentation.  Their forums appear to be well tended.  Again, the differences in results on the test torrents from the above was so slight that it will make no difference in real world use. Halite has a clean install with no addons etc.  Our Guides

Pros:  Low and stable RAM use.  Working versions had low CPU use.  Excellent performance on torrents.  Clean install, no addons etc.
Cons:  Has not  been updated in over a year, even though a good number (though a minority) of Windows users had issues.   Decent amount of private trackers accept its use, but not as many as Deluge and µTorrent.  Help resources need an upgrade.

Deluge made this list last time around for the first time, but its performance this time using the latest version was so poor that I almost removed it from the listing.  In reading their forums, it appears a good number of Windows users had similar issues. The Windows version of this freeware bittorrent client is not the primary focus of the development team and it does show a bit.  If you are going to use this client on a Windows system (and this article is for Windows users), then you should use version 1.3.1.  The other clients here (except for µTorrent) would not be accepted at most private torrent sites.  Deluge does have a good reputation and is accepted at most private sites.  Its forums, user guide and FAQ provide a good level of support.    With version 1.3.1, this client will perform as good as any of the above.   Deluge has a clean install, no addons etc.  Our Guides

Pros:  Cross platform client that is stable for the most part and efficient.  Well accepted at private trackers.  Excellent performance on torrents.  Good help resources.  Pretty wide acceptance at private trackers.  Clean install, no addons etc.

Cons:  Latest versions have severe issues for Windows users and are not recommended.

Transmission-QT (Windows) is not an "official" release of the Transmission team, but has been touted in their forums for years and recently moved to its own site.  Previous versions had issues for me and were not included in this review.  however, I was pleasantly surprised to find that this version has crossed the line to become one of the best bittorrent clients for Windows.  Its performance on the test torrents puts it on a par with all of the above in real world application, though it did fall slightly behind.  This version ran stable and efficient as well on both of my Windows operating systems.  Many users will find its simple interface appealing.  The help resources are limited, but for more savvy users this is an excellent choice.  Even for newer users, the setup guide that I have prepared will be all you need to get up and running well.  I tested at a couple of private trackers and this window version was rejected even though the mainline client Transmission was accepted there.  This port has a clean install, no addons etc.  Our Guides

Pros:  Efficient and stable with excellent speeds.  Simple interface.  Clean install, no addons etc.

Cons:  Not an "official" release of the Transmission team and is lacking help resources.

BitTorrent and µTorrent are both owned by BitTorrent, Inc., and are supposed to be identical.  Except for the name, the features and look are identical.  There were some small differences in RAM and CPU use on my systems, but these do not amount to much.  For years I did not list BitTorrent as it included a separate and unnecessary, for the user, program called DNA.  Even after removing DNA, the size of the BitTorrent installer was quite a bit larger than µTorrent's and that raised suspicions among myself and others that something else was being packaged.  The official word on that was that Bittorrent used an installer package and µTorrent did not.  In any event, the BitTorrent installer is now a tiny bit smaller than µTorrent's, erasing any doubts on this issue.  All the positives, and negatives of µTorrent's apply here.  This is a feature rich, small, efficient client that performs with the best as far as speeds.  The help resources are not quite at µTorrent's level, but really any of the µTorrent resources may be used for Bittorrent, so they are identically excellent there also.  Its performance on the test torrents was very slightly behind µTorrent's, but in practical use they are the same superior results.  BitTorrent was the original client created and if you like  the name better than µTorrent's, this is an excellent choice.  Although identical to µTorrent and owned by the same company, BitTorrent is not accepted at many, if any, private sites.  Our Guides

Update:  BitTorrent has gone back to the larger installer with the next build after my testing.  It is now 5.68MB as opposed to 538kB.  They are also enabling DNA at default.  I suggest disabling this at Options>Preferences>DNA.    I had them placed higher on this review due to their test results, but have moved them down due to the recent change.  Since it is identical in performance and look (except for name) to µTorrent, I will leave it on the listing, but I go back to my original position on BitTorrent: Just get µTorrent.  Thanks to "mrinmoyjk" for calling my attention to this.

Pros:  Excellent speeds on torrents, efficient and stable client with a large amount of features packed into a tiny package.  Excellent help resources.  Leader in the bittorrent field at the moment.

Cons:  Has had critical security alerts at Secunia. (now that it is essentially the µTorrent program-though none on latest versions).  Bing Toolbar install and search/home page change enabled at default on install. Unnecessary DNA program enabled at default and should be disabled in Options after install.   Not accepted at many private sites.  Also, an unnecessary "app" (changes from time to time) is offered during install (enabled at default).  Thanks to Gavin for pointing this out.  The toolbar, changes and app should all be rejected during install.

Excellent Clients

These two clients ran very well on the small and medium swarm torrents, but suffered on the large swarm torrents.  Each of these fell behind the above Superior clients in speed.  While the above were running above 1.5MBps, these came close to only 1MBps. I found that hard to believe as these two have been staples of the bittorrent scene for quite a while, but I tested this over and over and still reached the same result.  Still many users will like their features and interface and each of these has a loyal following.

BitComet has always suffered, unnecessarily in my opinion, from an image of a cheating, or poorly built client.  This has hurt their acceptance at private trackers although this has eased a bit.  The language issues of having a development team that is Chinese speaking only has hurt them over the years.  Still this is a solid bittorrent client with a small, but devoted, following.   The install does include a homepage change and a media player install enabled at default, but these can easily, and should, be rejected.  After install, one is still presented with self-promotional advertising which can be disabled, but is enabled at default.   I also find their interface cluttered with items that should be cleared up.  Their listing of torrent search sites would be agood feature if dead sites etc. would be cleared out (with some tinkering this can be done by the users).    They also do have their own LTSeed network as well as the ability to connect to other sources (which may help with torrents that appear dead) and http/ftp support..  They also have incorporated a provision to prevent duplicate sats to private trackers which should help users avoid "cheating" claims from the site.   But, BitComet does have a wide variety of options and for the most part runs stable.  They also have an excellent support structure through their two forums (CometForums and UniteTheCows (independent support forum)  and their wiki .(there is a nice FAQ at the Wiki).  In my test torrents, BitComet ran very well on all test torrents, but on the large swarm torrents did not reach the speeds of the Superior clients above.  Still, it is just a notch below and many people like the BitComet interface and performance as well as their varied source abilities.  Our Guides

Pros:  A stable and efficient client.  They offer a wide variety of features and excellent help resources.  Their torrent exchange, LTSeed network, support for other networks and support of http/ftp and other community features may interest some users and does make them unique among bittorrent clients in this regard.

Cons:  Still not accepted at a few private trackers (although this issue is rightfully being resolved) .  Home page change and media player program download enabled at default on install.  Self-promotional advertising banners and popups within client.  Performance on large swarm torrents was not at the level of the superior clients above.

Vuze  This once top flight program is definitely in decline.  This has become a back burner project for the development group as they are now involved in  the Fanhattan project. The plugins available from their days as Azureus are, for the most part, not being updated anymore.   Their forum has suffered as it is rarely attended by developers. The Vuze-Wiki is still an excellent help ressource, but it is also fading from lack of oversight.  Their install includes a toolbar and home and search page changes enabled at default.  There are also advertisements in the Vuze portion of the client.. macktone87 brought my attention to an important feature of Vuze.  As he put it "I haven't left Vuze yet because of its ability to be able to stream to pretty much any thing connected to the same router. I really enjoy watching videos on my TV, phone, I-Pod etc."  Its performance on the  test torrents this time was disappointing, though still respectable.  This is a decent client still, but its main attraction is its ability to stream to devices.   I also see many users who think that buying the Plus version of Vuze will improve performance.  The Plus version provides no additional features for bittorrent.  It provides a burner and anti-virus and you can get better free ones here at Gizmo's.  Bottom line, if you are not interested in the streaming, this client is not for you   Our Guides

Pros:    Streaming capability to connected devices.  Wide acceptance at private trackers.

Cons:  Lack of focus on bittorrent resulting in no major upgrades to that portion of their client in recent years.  The Vuze interface is useless for all but a few.  Bing Toolbar install and home page change enabled at default on install.  Advertisements within free version of Vuze interface.  Performance on large swarm torrents was not at the level of the superior clients above. 

Download Programs That Have Bittorrent Support

I received a good amount of comments regarding download programs that had recently added bittorrent support.  I have been testing such programs along with strictly bittorrent programs for several years and they always fail to reach the performance levels of the above programs.  Even if one already has a download program with bittorrent support, I would still suggest using any one of these seven programs for bittorrent.

There are guides for getting the best download speed for each of the bittorrent clients above, here at Gizmo's Tech Support Alert:

• Optimizing qBittorrent for Speed
• qBittorrent Additional Help and Information
• Optimizing  µTorrent for Speed
• Additional µTorrent Settings - Other settings in µTorrent
• Optimizing BitTorrent For Speed
• Optimizing Tixati for Speed
• Optimizing Halite for Speed
• Optimizing Deluge for Speed
• Optimizing Transmission For Windows For Speed
• Optimizing BitComet for Speed
• Optimizing Vuze (formerly Azureus) For Speed 
• Additional Vuze Settings - Other settings in Vuze
• Vuze Meta Search Adding Search Templates

After you have installed your bittorrent client and have set it up, you might want to check my articles

• Searching for Torrents (Popular Torrent Search Sites) for a listing of the most popular torrent search sites and their features.
• Finding Legal (and Free) Torrents which lists, with comments, sites that offer only legally downloadable and distributable content.