Optimizing µTorrent (or BitTorrent) For Speed

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Optimizing-utorrrent-speed-uTorrent-iconThis guide shows how to speed up downloads in the freeware bittorrent client,  µTorrent. All bittorrent programs need to have their incoming and outgoing communications flow freely in order to achieve the highest download speeds and that is what this guide is about.  This guide will also work for users of the BitTorrent client as the µTorrent and BitTorrent clients are identical.

This guide was put together using information given by the developers of bittorrent programs at their forums, guides and FAQs. There are no secret tricks, just the real basics of proper set up of a bittorrent program. Following these simple steps should result in increased download speed.

These are the basic principles of optimizing a bittorrent client, like µTorrent, for speed: 

  • Choose a proper port to avoid ISP blocks and conflicts with other programs
  • Forward that port through any software firewall and router to allow incoming connections
  • Adjust internal settings based upon upload capacity of the internet connection to allow room for outgoing communications and to distribute upload efficiently. 

There are some programs that claim to optimize speed in µTorrent.Such programs are a scam and generally contain adware or spyware. I have seen it said, by the developers of all bittorrent programs, that nothing will increase your download speed in a bittorrent client more than the basic steps set forth herein.

This guide will work for all versions of µTorrent and BitTorrent 6.1 (and later). Screen shots are from µTorrent 1.8.2 as the options menus had been changed starting with that version.

If you are looking to increase your download speed in µTorrent for Mac, see Optimizing µTorrent For Mac.

If you are not using µTorrent or BitTorrent, there are several other specific guides for other clients and a general guide here:
Optimizing Bittorrent Clients

There are several other help articles for and BitTorrent here at Gizmo's.  A listing is on this page:

µTorrent & BitTorrent Help

Choosing A Proper Port

To avoid messing up a network connection that is already cleared, first check and see if your communications are blocked or are already clear.  Have µTorrent running while you test the port.

The port that µTorrent uses is at Options>Preferences>Connection
The port number in your µTorrent should be entered at the port test site.
The Randomize port each start option should be disabled as this could affect router and firewall settings and rarely serves any useful purpose.


Enter the port number from your µTorrent here at the test page and press "Check":


Click to Test Your Port Success-just go to Adjusting Internal Settings.Error- follow all steps.

If you failed the port test above, then you should first set your port to a proper one.The most important choice here is to avoid using a port within the 6881-6999 range. This was the range originally used by bittorrent programs and is often blocked by Internet Service Providers (ISPs). (If your port was in this range, change and re-test).

The safest choice is a port in the 49160-65534 range as this will avoid ISP blocks and possible conflicts with other applications.  This range used to be 49152-65534, but apparently Vista and Windows 7 grabs some of those ports in between.   Vuze-Wiki: Port is Blacklisted

Windows users, if you want to make certain there is no conflict.  Go to the command prompt and type in netstat -a >c:\log.txt and the press "Enter".  This will check to see which ports are being used and save a text file called "log" at C:\.  Looking at the log.txt file, you will know which ports to avoid.

Forwarding The Port

A router will block incoming communications unless an exception is made. All software firewalls will block incoming communications and most will also block outgoing communications, unless an exception is made. If you are "firewalled", then other people will not be able to initiate connections with you (see Why Is Being Firewalled Bad).
As there are many firewalls and routers, this guide can not give explanations as to each. However, there are guides available, on the internet for most firewalls and routers and this guide will link you to them.

Software Firewall - The permission should be set to allow TCP and UDP in both directions. Generally, you will have a choice to set permission for the µTorrent port or for the µTorrent program. Setting permission for the port is the safer choice.
If you are using Windows Firewall, then all you have to do is go to Options>Preferences>Connection in µTorrent and enable the Add Windows Firewall exception option.

Otherwise, you can check these options for guides:

Router - There are two choices here.  The easier way is to use UPnP.  However, this has a possible security issue.  Using UPnP allows any program to create a port mapping through the router without consent of the owner.  Note:  Given the recent findings of Rapid7 regarding security flaws in UPnP, it is generally suggested here that manual forwarding be used.  If you still want to use UPnP, then it would be a good idea to test and see if your device is vulnerable to attack through UPnP.

The other choice is to manually forward the port through the router.  This does not have that security issue, but involves going through several steps to accomplish.  Using the guides linked herein, this should not be that difficult and is the preferred method.

UPnP (NAT-PMP in Apple) - The Easy Way Enable UPnP (NAT-PMP in Apple) in µTorrent and router.



Manual Forwarding-The Preferred Way

  1. UPnP (NAT-PMP) Must be disabled in µTorrent (see image above)
  2. Use the Static IP Guide
  3. Set permission for µTorrent port. This should be set to allow both TCP and UDP communications.
    You can check these options for guides:

Click Here to Re-Test Port Success-Proceed to next step. Error- re-do steps or seek help in Forums.  Have µTorrent running while re-testing the port.

Adjusting Internal Settings

The most important setting here is to cap upload in µTorrent to 80% of your overall upload capacity. Setting upload in µTorrent is a fine line. The more upload you give, the more download you will get from other peers. However, if upload is set too high, or to unlimited, then download speeds will suffer as outgoing communications (acknowledgment signals, resend requests etc) will be interfered with. Other adjustments are made here to distribute your upload so that you receive back the most download from other peers.

Note:  (Thanks to Roderunner for reminding me of this)

µTorrent does have a built in speed test and Setup Guide (Options>Setup Guide) that will automatically adjust settings in µTorrent. This is a slightly quicker process than this guide.  However, my testing of the Setup Guide settings versus the calculator of this guide showed better speeds with this guide. 

First of all, the setup guide only offers settings for certain upload rates.  So if your upload rate falls outside their offerings, the settings will not be as precise as those in the calculator below.  Even if your upload rate matches one of the offerings exactly, the automatic settings of µTorrent for that rate are not as effective as the ones given by this calculator.

There is not much more involved in entering the settings from the calculator into µTorrent and the increase in download speed will make it worthwhile.

Speed Test: Speedtest.net (Click for Test)
First the upload capacity of your internet connection must be determined by taking an online speed test. Speedtest.net has test locations worldwide and will highlight the one closest to you.
To take the test you must have Flash installed and javascript enabled.

Before taking the speed test, press Settings in the upper right of the speedtest.net page.  This will take you to another page.  At the bottom of that page is the "Global Settings" options.  Set "Speed Measurement" to kilobytes and press "Save" .  This will facilitate entry into the calculator below and will lessen confusion as µTorrent shows speeds in kilobytes.





You should stop all internet activity, including torrents, before taking the test and the test should be taken a few times to obtain a reliable average. Results will now show in KiloBytes. It is the upload rate that is important here.


Another Way To Test Upload Speed
For most people these test results will be reliable (Comcast users see Note). However, you may wish to do a double check on real life upload speed. When you are active on a torrent with a good number of peers and you are using your upload cap, set upload to unlimited and watch for about 5-10 minutes and see where upload settles in at. Then input that number into the calculator in the kiloBytes section. 

Note: Some ISPs will show inaccurate results on the speed test. If your ISP has anything like Comcast's PowerBoost, then your results will show higher than the actual speed of your connection. PowerBoost provides a burst of download and upload speeds above your provisioned download and upload speeds for the first 10MB and 5MB respectively. Since the speed test involves relatively small files, this will skew results upward.
If you have PowerBoost, or something similar, my findings from my own results and those of others is that the actual speeds are 60% of the test result.  So if you get 200kB/s for upload at the test, you should enter 120 in the kB/s box in the calculator.  Using Google ("speed result" x .6) will get the proper number to enter in  the calculator and this actually turns out to be very accurate.  You should end up with the calculator showing a cap that is about half of the test result.

Calculator Azureus Upload Settings Calculator
Once you have an average upload speed for your connection go to the online Azureus Upload Settings Calculator. Although designed for Azureus, this calculator will work for all bittorrent clients.
This calculator was created by the8472 a contributor to Vuze (fka Azureus) and part of the team that created Bittorrent Protocol Encryption.

Enter your average upload speed in the appropriate box


The calculator will automatically give the proper figures to adjust various options in µTorrent.


Input Results Into µTorrent - Screen shots of locations in µTorrent of settings to be adjusted 



Peer Sources & Encryption

Having the proper peer sources enabled, such as Peer Exchange (PEX) and Distributed Hash Table (DHT), will help download speeds as they will help you find additional seeds and peers for a torrent.  Local Peer Discovery should be enabled as it supposedly searches for peers on your ISP or those on an extended network or on a LAN party. it can be very useful on a LAN party.  I have not found it to make much of a difference when not on a LAN or extended network.

Encryption was primarily designed to thwart Internet Service Providers interference with bittorrent.  Having encryption enabled and allowing incoming legacy (non-encrypted) connections will provide you with the largest pool of seeds/peers to select from.

These settings are at Options>Preferences>BitTorrent and should be set as in this image:


Good Torrents

The general rule here is to choose torrents that have a high seed to peer ratio. Seeds have 100% of the content associated with the torrent and are only uploading to peers. Peers also upload to other peers, but are also looking for other peers to upload to themselves and their download capacity is almost always higher than their upload capacity.

This applies even though one swarm has significantly more active users than another. For example, a torrent with 30 seeders and 70 peers (30% seeders) will generally be faster than one with 500 seeders and 2500 peers (20% seeders) as the average upload capacity available to the peers will be higher. (TorrentFreak).

For more information see Good Torrents

Related Articles

Gizmo's Best Ever Freeware Forums

If you still have issues after using this guide and would like some assistance, you may post here or our Forums.  The comments section here is not well set up for ongoing discussions, so the forums are a better place.

When posting on a speed issue, please provide

  • Your speed test result for both upload and download speed in kiloBytes per second (kBps)
  • Your result at canyouseeme, both before taking any steps and after.  Just indicate Success or Error do not post your IP address.

If you have a suggestion or correction for the guide, please post here.

Those who wish to post a thanks may post here or in the forums. I always appreciate hearing from those who this helped and I do read the posts regularly. I used to respond to each thanks, but realized it was clogging up the comments section. I thank all those who have posted their appreciation and all those who will.

So, to those who post a "Thanks", I appreciate it.



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by kittydeluxxe (not verified) on 18. October 2012 - 18:47  (101009)


I feel like I've tried everything; including opening the port on my router.

I've run the speed test at Speedtest.net with the following results:
download = 25.03Mps and upload = 3.63Mps

The test at http://www.canyouseeme.org/ is Error: I could not see your service on XX.XX.XX.XX on port (50076)
Reason: Connection timed out

Any suggestions?

by ghettocandy (not verified) on 18. October 2012 - 14:01  (100991)

thank you! so easy to follow, i did everything you said and as soon as i hit APPLY instantly the seed numbers changed and my download times were cut by at lEAST half! :) you're my hero

by sahilhamal (not verified) on 15. September 2012 - 3:47  (99279)

no help.nothing changed on mine.it was around 20 and still around 20

by kothasanju on 30. July 2013 - 16:51  (109769)

its working alright ive tried it and my speed increase to 300 so try again doing it

by Eve_is_giving_up (not verified) on 3. September 2012 - 16:27  (98705)

I really dont know what to do anymore. All the tests are positive, all settings are as they should.
I am getting 2MB/s or higher download speeds when downloading a torrent from a private site which only hosts very specific content (Poker-related videos, extremely well seeded), but every other popular site only gives me between 1-10kB/s (TPB, extraT), even when I choose well seeded torrents (e.g 2000 seeders, 1000 leechers).
It started when I got a new PC and switched to win7, but that might not be important, since I still get good speeds, but only at one specific site.
Or maybe it is important after all, because my upload speeds suck on every site now (started when I got new PC), 10-20kB/s max, even though speed test results show me approx. 3000kB/s down and 750kB/s up.
What can I do? I tried for months now, but no results.

by Eve_is_giving_up (not verified) on 4. September 2012 - 11:38  (98741)

One more thing that might be of significance: Whenever utorrent is running for longer than, say 1h, all other internet traffic (browser, etc) is stopping and I get an error message when opening the brower ("no internet connection"), yet utorrent is still getting connections and slowly down and uploads the files. Just all the other programs cant connect to the internet anymore.

by Teneye (not verified) on 11. August 2012 - 0:52  (97527)

I followed this guide thoroughly and down everything.
My ports are showing as opened and my speedtest is showing up to 30MB dl's and 200+kB/s upload, but still i'am only getting average 8kB/s - 50kB/s if that. Its weird, sometimes(and not much) it does get a boost and i have seen myself getting speeds of almost 2MB/s in bittorrent, but that lasts seconds then kicks all the way back down to 50kB/s and lower.
I'v been trying to monitor the peers list, and from the looks of it i'am connected to atleast 10 peers that are only sending an average of 0.4kB/s, and i only ever get 1, sometimes 2 peers that send a "decent" amount.

I was just wondering if you could help me at all?

Thank you very much in advance

by mr6n8 on 11. August 2012 - 12:13  (97551)

That sounds like it might be some ISP (Internet Service Provider) interference.
Who is your ISP?
What port number are you using in BitTorrent?

Also, that is quite a wide difference in up and down speed capacity. Are you sure of those test results?

by Ten Eye (not verified) on 11. August 2012 - 14:39  (97559)

Hey thanks for the reply.
yeh i'v done a good few speedtests now, and it's mainly sitting at the 32Mbps download and 1.88Mbps upload.
ISP is Virgin Media on the 30MB package, and i'am using Port: 49160

by Anonymous1234 (not verified) on 15. September 2012 - 10:23  (99294)

how to find port number plzz reply me soon(eg. 27017) dis type of ports

by mr6n8 on 11. August 2012 - 15:12  (97562)

Virgin does do some throttling (if you can make sense of their traffic managment page), but it should not be to the extent you are experiencing.

Have you tested 49160 at canyouseeme and have it pass?

Not that it has anything to do with your issue, but to use this guide you should change the output the speed test to kilobytes.

Have you enabled encryption as set forth in the guide?

by Ten Eye (not verified) on 11. August 2012 - 23:00  (97583)

Hiya there thanks again for your reply.
yeh i'v tested it at canyouseeme as well and its all showing up as open.
yeh i have read that they do some throttling but thankfully as u just said not to the extent as i'am experiencing.
Yeh sorry I did actually have the test output as kilobytes i was just for some reason outputting it to you in megabytes :p
Yeh i followed the peer sources & encyption part of the guide spot on also.

by mr6n8 on 12. August 2012 - 10:35  (97596)

That is good, but it makes it harder to figure out what is going on.

The drop you are experiencing, does this happen on all torrents and from different sites?

Try this LibreOffice torrent and see if the drop in speed happens. Click on the word Torrent for the Main Installer. This should go to high speeds quickly and on mine the speeds stay up.

by Ten Eye (not verified) on 13. August 2012 - 0:30  (97629)

Ok so i'v got a bit of an update.
I dug out my old laptop as i'v recently been using my partners, so i dug out my old laptop, booted up utorrent and tried downloading the exact same torrent as i was downloading on the other laptop, and i was getting download speeds of on average about 1 - 2MB/s. Just downloaded that libreoffice on the same (old dug out laptop)and i was getting a speed of on average 3.5MB/s.
So, i guess its nothing to do with the settings of utorrent or the router/ISP, its got something to do with my partners laptop :/ I have no idea what it could be :S
Any ideas?

by mr6n8 on 13. August 2012 - 1:12  (97630)

That is good news.

A lot of security softwares now have some sort of web "protection" that may interfere with bittorrent. I know MalwareBytes added something (though I do not think it would interfere the way your issue is). So any security software can possibly cause an issue.

Anyhow, it could be one of the other security softwares on that computer.

What are the security softwares on the computer with the issue? (or just google the name of the security software and uTorrent)

by Ten Eye (not verified) on 13. August 2012 - 23:47  (97674)

It AVG that is installed and active, which is exactly the same as what i have on my laptop(the one thats downloading great)
I also tried disabling the firewall etc. and still nothing :(

by mr6n8 on 14. August 2012 - 13:12  (97697)

The firewall will not be the issue. The firewall is an issue on open port and your port is open.

The problem will come from other parts of the security. If you have AVG security suite, I believe there is a Instant Messaging and P2P downloads protection within the antivirus. Check and compare the settings there between the two computers (try disabling on the low speed computer anyways).

There may also be an issue within their LinkScanner protection, though I have not seen anything on this. If the above does not resolve, try disabling this.

by MidnightCowboy on 14. August 2012 - 5:01  (97680)

This is possibly unrelated, but I wonder which adapter it is reading the speed from? Try this program, selecting the different adapters listed one after the other to see if different speed readings are given.


by Dodasilvas (not verified) on 10. August 2012 - 2:07  (97486)

mr6n8 ,
The "uTorrent speed Test" was succesful but the icon remains yellow...why ?
many Thanks.

by Dodasilvas (not verified) on 10. August 2012 - 2:09  (97487)

i meant "uTorrent Setup Guide"...

by mr6n8 on 10. August 2012 - 7:49  (97499)

The setup guide has 2 parts, Bandwidth and Network.
Did you pass the Network test?

by Abhi (not verified) on 9. August 2012 - 16:42  (97473)

Hi I was just following the steps and got stuck at one point where thy have mentioned to type netstat -a >c:\log.txt in cmd even though I did that nothing happened 1st it said denied when I ran cmd through administrator nothing happened. so help me!!!

by mr6n8 on 9. August 2012 - 16:55  (97475)

I guess I forgot to say "press enter" after typing that in.
There is a space between netstat and -a, but after that no spaces.
It should go to a new prompt (after some delay).

At that point a text file should be at your C base.

Did you check to see if a text file was created?

But before that did your port test fail for the port you had set in uTorrent?

by Abhi (not verified) on 10. August 2012 - 6:09  (97495)

Yes I waited but nothing happened. I even pressed enter. Here is a rookie question "How to find which port num will be make my port open???" coz when I ran the inbuilt test it showed " port is not open but you are still able to download?"

by mr6n8 on 10. August 2012 - 7:47  (97498)

No port will show open unless exceptions are made in any firewalls, software or hardware (router), on your system. The 2d part of the guide, forwarding the port, deals with that.

As to the port number to use, not sure why the netstat is not working, but that only shows which ports are in use by other programs. Just choose a port within the 49160-65534 range and set the exceptions.

EDIT: As to the netstat, I will point out that there will not be anything that shows in the command screen. There will be a text file created at C:\. The command screen should return to a prompt.

by Abhi (not verified) on 11. August 2012 - 5:12  (97533)

Hi I found a notepad with name log and it contained these lines:
Active Connections

Proto Local Address Foreign Address State
TCP Homepc:50910 TIME_WAIT
TCP Homepc:50932 TIME_WAIT
TCP Homepc:50941 TIME_WAIT

Is this what you were trying to say. And should I choose a port number that is mentioned here or in between these number like 50931. I even made an exception in the fire wall.

by mr6n8 on 11. August 2012 - 12:10  (97550)

Yes that is the file I am talking about.

Those are ports that are already being used and should be avoided. I would suggest using a port away from those but in the 49160-65534 range, like 51565.

by Abhi (not verified) on 11. August 2012 - 16:16  (97565)

first of all thank you for replying and cooperating. and what are the meaning of these

by mr6n8 on 11. August 2012 - 16:37  (97567)

LISTENING - waiting for a connection request from any remote client

TIME_WAIT - Represents waiting for enough time to pass to be sure the remote peer received the acknowledgment of its connection termination request.

ESTABLISHED - The port is ready to receive/send data from/to the remote peer.


by swirlip on 6. August 2012 - 12:22  (97285)

just commenting to say a quick thanks, download speed now increased to nearly 4mb/s. god bless fibre optic broadband, im lucky with my internet speed i know! and god bless mr6n8 for making it faster hahaa xD

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