Which BitTorrent Client Is the Fastest?

Fastest BitTorrent Clients - The Tests - A Comparison of Speeds in Realtime

Every BitTorrent software developer claims that theirs is the fastest BitTorrent client, but which one really IS the fastest? There are so many variables to be considered: Seed/peer ratio of individual torrents, public or private trackers (and number of trackers in a torrent), DHT “trackerless” support and UPnP port forwarding, just to name a few. Even the default “factory” settings of each client can have an big impact on download speeds.

So how it is truly possible to really know? Conduct speed tests in a controlled experiment, natch! Let’s put ‘em to a test!

About The Tests

To create a semi-controlled environment in which the data could realistically be used, we needed to conduct the experiment in realtime - in a scenario where ALL BitTorrent clients were using the exact same torrent (loaded simultaneously in each) and thus were ideally downloading at the same time. Not only that, but we repeated the same text three times with 3 different .torrents (all 5 clients were loaded with the exact same torrent at the same time, on three separate occasions).

OK, no peeking - don’t scroll down to the bottom just yet. Out of the five tested clients (µtorrent, BitComet, Azureus, BitTorrent and BitLord), which one do YOU think won the races?

The Variables

To cut down on some of the variables, we used the same torrent for each, from the same source ( thus the trackers in the torrent would remain identical (and any changes to the tracker and seed/peers would be reflected identically for each in real time). We also “tweaked” the settings of each client to try and maximize speeds. Here’s what we attempted to do within each of the five BitTorrent clients, prior to running the torrent:

  • Set each to “maximum” download speed.
  • Set each upload speed to 50KB/s.
  • Enabled DHT and UPnP where possible.
  • Different port numbers (obviously) needed to be used, but we stayed within the good range for each client.
  • Attempted to re-create the same ’settings’ environment through advanced connectivity options. Where applicable, each clients’ settings were modified to reflect these similar environments:

Although we conducted these tests using three different popular torrents, we only ran one torrent at a time for all of the clients. This ensured that we’d be able to achieve maximum or close-to max swarm speeds for each client during simultaneous downloading. The .torrent file itself is probably the most important constant of the experiment, which is why we chose to use the same torrent for all five (on three different occurences).

The Tests

We elected to use five different BitTorrent clients, and three different torrents to use in each. Also note that we (and so should you) have Peer Guardian 2 running during these tests. HTTP was allowed, and here are the blocklists we used:

The BitTorrent Clients

For the software, we wanted to provide the TOP 5 BitTorrent clients (in terms of usage and popularity). The first four in the roundup are no-brainers, but for the fifth one we relied on comparing alexa traffic rank data with number of downloads. In our opinion, BitLord rolls in at #5 (although this is debatable). Here’s the 5 clients we used in the testing:

The .Torrent Files

For the *.torrents, we needed to supply an equal playing field for each client. To achieve this, we chose 3 different torrents from (using public trackers). This would ensure that each client used the same publicly available torrent with the exact same trackers in each. Seed/peer statistics would thus be updated simultaneously for all clients.

We also opted for torrents that are proper “scene releases” listed on dupecheck websites (therefore eliminating the chances for anti-P2P tampering or amateurish uploads). Also note that all 3 torrents were one week old, in order to smooth out the highs-and-lows of seed/peer ratios normally associated with newly-released torrents. Here’s the 3 .torrents we chose:

  • Rambo.IV.REAL.PROPER.R5.xVID-UNiVERSAL.4041898.TPB [mininova].torrent
  • Sleuth.LIMITED.RERIP.DVDRip.XviD-DMT.[] [mininova].torrent
  • Bee.Movie.DVDRip.XviD-DiAMOND.4041897.TPB [mininova].torrent

The Results

Here are the results! All speeds are in KB/s.

BitTorrent Client Test #1 - Bee Movie Test #2 - Rambo Test #3 - Sleuth Average D/L Speed:
µtorrent 35.3 39.0 30.3 34.9
BitTorrent 31.9 30.9 25.4 29.4
Azureus 44.0 39.1 28.8 37.3
BitComet 55.0 40.0 29.9 41.6
BitLord 51.0 39.0 31.0 40.3

Azureus is the only client that doesn’t show a statistic for the “average” download speed of completed torrents. Instead, it shows data for the “time” it took to complete a torrent, in hours and minutes. To calculate the average download rate, for example - Bee Movie is 714.0 MB with a “Finished in” time of 4h 37m, we had to derive the KB of the file and divide it by seconds. 714 X 1024 = 731136 (total KB) divided by 4h 37m (277 minutes X 60) = 16620 seconds. Therefore the average download speed was 731136 / 16620 which equals 43.99 KB/s.

The winner? In our tests, BitComet is the fastest BitTorrent client. No surprise here, we could’ve already predicted that. It’s little wonder - BitComet has been banned by most private trackers for being a “dirty” client, and uses aggressive settings & features to maximize downloading.

NOTES: BitTorrent (the original Bram Cohen’s BT client) came in a dismal fifth place, and in all three torrent examples it was the last client that hadn’t finished downloading - to help it out, we removed the “seeding” torrents from all other clients so that it could finish downloading on it’s own with maximum bandwidth. If we hadn’t done this, BitTorrent’s speeds would have been even lower. µtorrent: We were surprised that it came in fourth place. Perhaps the version number may have had a factor - we used v1.6.1 (a private-tracker ‘friendly’ build number).

May this put your mind at ease!

  1. Blaenk Denum Says:

    I think DHT should have been off. There was no reason to keep it on and it just added to the variability of the tests. Also, BitComet shouldn’t have been included in the test due to it’s notorious reputation. It’s like saying that the winner is a client that cheats its way to the finish line, and what’s worse is you know it.

    Like you noted, it is really difficult to benchmark any one client, for there are too many variables involved. I’m pretty sure you set the same options for most clients (Max number of connections, etc.), but there’s also the question of how many peers/seeds each client gets to connect to compared to any other client at any given time. Not to mention the bandwidth is being split four-times among each client (And that’s assuming you aren’t running anything that uses the network in the background or during the tests), and there could be a question of QoS regarding whether or not any one client hogs more bandwidth by marking itself with a high priority.

    Anyways, you’re one of the few sites that really talks about these things in an informative manner, so keep the articles coming! I didn’t mean to come off as a nitpick, just thought I’d say these things anyways for any other readers to take into consideration (Rather than having everyone rushing to get BitComet). Perhaps a comparison of these clients would’ve been better. Regarding their system resource usage, their size, speed (In execution and possibly bandwidth), their features, options, and reputation (i.e. BitComet is banned by many trackers for ‘cheating’, etc.), platform support, and any other things that could be compared.

  2. sharky Says:

    Thanks for the feedback! That’s what this is all about - I’m thrilled someone contested these results!

    It’s truly (almost) impossible to conduct these tests across an even playing field. What I could have done was just run one client at a time, with one torrent. But I didn’t want to wait (up to) 15 days for three torrents, (plus, I wouldn’t be able to download my OWN stuff during the tests if I performed it that way). The other reason why this “one-at-a-time” test wouldn’t work is that by the time I got around to the last BitTorrent client, the seed/peers in the torrent would have totally changed, (generally this would lead to an unfair impact on the last client being tested - as the S/L count would be lower, in most cases). Anyways, in these tests nothing else was consuming bandwidth - I had no other torrents, P2P programs or even browsing going on at the same time (as I did these overnight on three separate nights).

    I was actually a little surprised by the lack of speed for all results. I have a 1.0MB download connection (8.0 Mbit) and can often get 400-500KB down rate for good torrents (such as these). Only the “BEE MOVIE” torrent cracked the 200KB/s (average) download rate through all clients simultaneously. I forgot to mention that I had Peer Guardian 2 running at the same time, as well. I’ll edit the article and add that in.

    This experiment is really more about ‘benchmarking’ them against each other, and see which one leads the pack. To make this test REALLY work, you’d need to have 5 similar computers hooked up to different Internet connections (with each connection being the same “ISP-subscribed” package). Even this would be suspect - no upload/download rates are ever what the ISP tells you, (there are other variables - distance from server; how many “people” are in your area on the same cable ‘pool’, etc.).

    Me, personally, I use BitComet for public torrents (mininova, thepiratebay) and I use utorrent for the private sites - but lately I can’t be bothered with BitComet anymore and just use utorrent for all. Often lately I’ve been utilizing ONLY private trackers, due to all the crap on the public sites, nowadays. Most tech-savvy BitTorrent users know better than to use BitComet, except on the public trackers.


  3. Wendy McKee Says:

    I can’t thank you enough for this very useful information. I am on dial-up (sucks) but have no choice given that I live in the boonies. Anyway, thanks again. You are awesome for doing all of this work for me (and others who have read).

  4. Trackback :: Bittorrent » Which BitTorrent Client is the Fastest?

    […] sharky wrote an interesting post today on Which BitTorrent Client is the Fastest?Here’s a quick excerptEvery BitTorrent software developer claims that theirs is the fastest BitTorrent client, but which one really IS the fastest? There are so many variables to be considered: Seed/peer ratio of individual torrents, public or private … […]

  5. Diji1 Says:

    Another fantastic article on a great site: truly, this is my favourite P2P site handsdown, I’ve learnt so much!

    I wonder if testing the clients across a LAN would tell us anything - it would at least eliminate the internet variablity issues.

  6. valavan Says:

    i think as bitcomet has been included, you should have tried “netexpress”, “flashget” and limewire.
    these softwares are on and average 2folds faster than bitcomet.

  7. NikkyMY Says:

    To me the fastest bit bit torrent client is Xunlei Thunder 5 chinese version that only usefull on public and some private tracker (little) its use http header …function like normal download and isp cant even trootle it .This torrent will consume your bandwith like hell if download speed unlimited . Beware ..wanna try this one go this link .In the blog one no ad version. Good luck trying !

  8. ulupu stew Says:

    In reply to blaenk… this case its not the matter of how it gets to the finish line, rather how fast it gets there. In reality how can there be cheating without rules??And how is there rules in an illegal action such as downloading movies? LOL

  9. ulupu stew Says:

    Also….I use Limewire to download my torrents. How come you didnt include that in the tests? I am curious as to how much faster them clients are opposed to mine.

  10. ulupu stew Says:

    sorry for the amount of posts but i just would like to add Get rich or die trying is currently downloading from a torrent at 157kbs.

  11. kay Says:

    its true bitcome is faster. i downloaded winrar to 2 clents utorrent and bitcomet. utorrent took 8 minutes while bitcomet finished it in 1 minute and 10 seconds. i still slike utorrent because it is more lightweight. if utorrent makes their setting like bitcomet i would really like it.

  12. kay Says:

    Utorrent is looong. if you have a shit out of date computer then its best for you to use utorrent to save memory. but those who have modern PC bitcomet is the best. i cant be asked to us utorrent it just makes my fricking brain go mad because its takes so frickin long to download. even though i still like utorrent.

  13. Dj_Prathik Mixx Says:

    Hey Utorrent is good, trustable..n i prefer it coz it has the easiest options n also u can resume ur downloads easily by choosing the download location after an XP or vista installation….kewl software hav admired it fo years……

  14. rocksinthecreek Says:

    Iunderstand uTorrent is now owned by an anti-p2p group. They were bought by BitTorrent Inc., and your computer checks in with them when you run it . I don’t fell very good about using it anymore, and the alternatives aren’t great. I’m not sure what to use - Deluge won’t work on my old W2000 torrent machine.

  15. AJITH Says:

    ya, that s true…
    BitComet slightly faster than the other torrent software….

  16. DowloadManiac Says:

    i think the fastest torrent client is Xunlei a.k.a Thunder5 that is download speed about 100-300kb/second.Amazing right?

  17. ME Says:

    This comparison suffers from the same exact problem I mention here:

    Even if you cut down on the variables, you don’t necessarily make the experiment controlled. Unless it’s *actually* controlled, the results of the experiment should be taken with a grain of salt, as other factors outside of the clients’ control can (and will) affect the outcome.

    That’s not to say that the experiment doesn’t provide interesting results, but it means that you can’t take away from the experiment any absolute fact about which client is fastest.

  18. ninja Says:

    For a controlled environment, it would have been better to upload a torrent using an open tracker, and 2-3 seed boxes to seed it.
    Then add the tests to the clients (with all peer sharing methods disabled), and let each client individually run through the torrent. once the torrent is complete, record the data, stop seeding it on the client, and run he same torrent on another client.
    This would reduce chance results to near zero, and provide genuine data on actual client speeds, since the peers wouldn’t change, the client’s cant effect each other’s speeds, and everything is identical for every trial.

  19. murtaza Says:




  20. Amt Says:

    bitcomet is the fastest torrent client.
    i have used many client but i get maximum speed with bitcomet.
    i done a simple experiment i started my downloading file after blocking port , even after blocking port bitcomet was giving best speed where as others speed was approx 1-2 Kbps.

  21. pepe(fahad) Says:

    thanks man

    very nice info

    i used to use flash gate its very fast but it has a lot if problems with security such as spy wares etc…

    thanks a lot for the information

  22. parag Says:

    ya ur rite its fastest but still it cannot beat xunlie heres the link

  23. Rapidshare Search Files Says:

    I don’t love Torrents! Rapidshare (or mediafire or hotfiles) is much better solution!

  24. mj Says:

    is dere any other site other thn torrent ??????????

  25. Ht Says:

    Hey im using vuze (azureus) with an internet connection of 1 mb and my download speed on a good torrent stays above 100 kbps. is that max or should i change my torrent client to bitcomet or xunlie?

  26. TV Says:

    I have to disagree that bitcomet is the fastest. I downloaded the same game from the same site with the same amount of seeds with bittorrent and then bitcomet and it took 30 minutes longer with bitcomet!! I am not impressed.

  27. Weak Article Says:

    Reading these comments explains why you idiots belong on public trackers. God you people are fucking stupid, and have no clue about what “fast” downloads are all about.

  28. neonsonicboy Says:

    I’d say that Transmission is fastest. µTorrent managed about 10Kbps, but with Transmission I am getting about 220 Kbps, and my internet connection isn’t very fast at all; 200K is about what I get when doing most direct downloads.

  29. Su B Says:

    I think Bitlord actually uses Bitcomet architecture in the background perhaps without that much aggressiveness; as it created several registry entries in the name of Bitcomet in my machine.

  30. StealthyPancake Says:

    Three tests is a really small test size. Problem with this test is it all depends on what computer resources you get and what seeders each application receives. It would be better if you downloaded the same file 10 times for each application, running each application by itself. One program may just be better at stealing resources from other process on your computer and that is why the download speed is higher. I don’t know that is just my thoughts.

  31. Saturn3672 Says:

    Thaxxxxxx A lot guys.!

  32. M2 Says:

    yeaaaah!bitcomet’s the best
    i had torrent files that they’ve never been downloaded
    in a article i read that bitcomet is the fastest
    it was

  33. rick Says:

    bitcomet is the fastest. i get between 200-2000kbs with torrents

  34. ozzy Says:

    shit these tests are old

  35. Aeso Says:

    This is all crap, i use Bit torrent, it is fastest, i download at over 600 kb per second w it. go to canada

  36. Carlosmano Says:

    VUZE is the fastest dickheads. ALL of you are fucking stupid with bittorent or bitcomet because vuze is the best of all that crap.

  37. Samrat Kothari Says:

    thnx a lot.. not only it gave a fair idea abt torrent speeds but also at highlighted the factors influencing and torrents dependence on them..

  38. upnorth Says:

    I use bitcomet and I download at speeds of, at the very least, 1500kbps. So I don’t know what you people are all doing wrong. I see a commercial for a new dvd out and I’m watching it in HD before family guy is back on. By the way xunlei is garbage unless you are from china. utorrent is probobly the second best in my book but thats for people with old computers or dont want to take up much resources.

  39. ryan Says:

    ok heres the thing all of these are crap
    i use Bitspirit and get a constant 1.12mb thants over 1000kbps dosnt matter what im downloading if its a 11GB game or 10mb program after about 5-10 mins i get full speed most files after 30 seconds i get max out.

  40. ritterderzodiac Says:

    Xunlei Thunder didn’t came in the test and with it the abc modification TOPBT

  41. krish Says:

    u r the ginious

  42. jocuri noi Says:

    I’m impressed, I have to say. Really rarely do I come across a blog that’s both informative and entertaining, and let me tell you, you’ve hit the nail on the head. Your blog is outstanding; the issue is something that not enough people are talking intelligently about. I am really happy that I stumbled across this in my search for something relating to it.

  43. Michael Says:

    Thanks for the great info. One thing that has annoyed me with torrent clients is the double downloads needed to download using torrents…. First download the torrent file and then download files using the torrent with a torrent client.
    I found an easier way with SKDownloader torrent client few weeks back. It has a firefox extension(and internet explorer extension as well), that will give you a “Download with skdownloader” in the browser right click menu. If you use this on a torrent link, SKDownoader will download the torrent and start downloading files using the torrent automatically… Looks pretty cool… :)

  44. sunny Says:

    i am using bitlord. it is quite good then utorrent. i used many other softwares e.g p2p pro, rocket pro, fast torrent, but bitlord is best. But as per above results i will try bit comet.

  45. halloween Says:

    all above expmts are not meaningful until u consider the “source file’s own health”
    i mean to say some files get corrupted ,so downloading takes time, 2nd thing is the seed leach ratio, more the seed to leach ratio, better is the speed,

    in all these clients, once u alter seeding options, u speed falls,,

  46. rofl Says:

    bitcomet is the fastesti downloaded 4 gigs in 2 hours.416 kb really are fast.On u torrent or bittorent it took me weeks.