General questions:

Compilation and Installation:

Tor Browser Bundle:

Advanced Tor usage:

Running a Tor relay:

Running a Tor hidden service:

Anonymity and Security:

Alternate designs that we don't do (yet):



What is Tor?

The name "Tor" can refer to several different components.



How is Tor different from other proxies?




Doesn't the first server see who I am?
Can't the third server see my traffic?

What programs can I use with Tor?

There are two pieces to "Torifying" a program: connection-level anonymity and application-level anonymity. Connection-level anonymity focuses on making sure the application's Internet connections get sent through Tor. This step is normally done by configuring the program to use your Tor client as a "socks" proxy, but there are other ways to do it too. For application-level anonymity, you need to make sure that the information the application sends out doesn't hurt your privacy. (Even if the connections are being routed through Tor, you still don't want to include sensitive information like your name.) This second step needs to be done on a program-by-program basis, which is why we don't yet recommend very many programs for safe use with Tor.

Most of our work so far has focused on the Firefox web browser. The bundles on the download page automatically install the Torbutton Firefox extension if you have Firefox installed. As of version 1.2.0, Torbutton now takes care of a lot of the connection-level and application-level worries.

There are plenty of other programs you can use with Tor, but we haven't researched the application-level anonymity issues on them well enough to be able to recommend a safe configuration. Our wiki has a list of instructions for Torifying specific applications. There's also a list of applications that help you direct your traffic through Tor. Please add to these lists and help us keep them accurate!

Why is it called Tor?




Is there a backdoor in Tor?

There is absolutely no backdoor in Tor. Nobody has asked us to put one in, and we know some smart lawyers who say that it's unlikely that anybody will try to make us add one in our jurisdiction (U.S.). If they do ask us, we will fight them, and (the lawyers say) probably win.




Can I distribute Tor?




Most people who ask us this question don't want to distribute just the Tor software, though. They want to distribute the Tor Browser. This includes Mozilla Aurora and Vidalia. You will need to follow the licenses for those programs as well. Both of them are distributed under the GNU General Public License. The simplest way to obey their licenses is to include the source code for these programs everywhere you include the bundles themselves. Look for "source" packages on the Vidalia page and Mozilla Aurora pages.



How can I get support?

There is no official support for Tor. Your best bet is to try the following:

  1. Read through this FAQ.
  2. Read through the documentation.
  5. Send an email to These are volunteers who may be able to help you but you may not get a response for days.

If you find your answer, please stick around on the IRC channel or the mailing list and answer questions from others.

Is there a Tor forum?

Not yet, but we're working on it. Most forum software is a disaster to maintain and keep secure, and at the same time too many of the Tor developers are spread too thin to be able to contribute enough to a forum. As of June 2012, we have a funder who wants to help us do it right. Stay tuned! (Tickets 3592 and 5995 relate to forums too.)

Why is Tor so slow?

There are many reasons why the Tor network is currently slow.




What can you do to help?

  • There are some steps that individuals can take to improve their Tor performance. You can configure your Firefox to handle Tor better, you can use Polipo with Tor, or you can try upgrading to the latest version of Tor. If this works well, please help by documenting what you did, and letting us know about it.

What would The Tor Project do with more funding?

The Tor network's several thousand relays push over 1GB per second on average. We have several hundred thousand daily users. But the Tor network is not yet self-sustaining.

There are six main development/maintenance pushes that need attention:

  • Usability: Beyond documentation, we also need to work on usability of the software itself. This includes installers, clean GUIs, easy configuration to interface with other applications, and generally automating all of the difficult and confusing steps inside Tor. We've got a start on this with the Vidalia GUI, but much more work remains — usability for privacy software has never been easy.







What are the SSL certificate fingerprints for Tor's various websites?

    * SSL certificate from Digicert:
    The serial number is: 02:DA:41:04:89:A5:FD:A2:B5:DB:DB:F8:ED:15:0D:BE
    The SHA-1 fingerprint is: a7e70f8a648fe04a9677f13eedf6f91b5f7f2e25
    The SHA-256 fingerprint is: 23b854af6b96co224fd173382c520b46fa94f2d4e7238893f63ad2d783e27b4b SSL certificate from RapidSSL:
    The serial number is: 00:EF:A3
    The SHA-1 fingerprint is: 50af43db8438e67f305a3257d8ef198e8c42f13f

How do I uninstall Tor?

This depends entirely on how you installed it and which operating system you have. If you installed a package, then hopefully your package has a way to uninstall itself. The Windows packages include uninstallers. The proper way to completely remove Tor, Vidalia, Torbutton for Firefox, and Polipo on any version of Windows is as follows:

  1. In your taskbar, right click on Vidalia (the green onion or the black head) and choose exit.
  2. Right click on the taskbar to bring up TaskManager. Look for tor.exe in the Process List. If it's running, right click and choose End Process.
  3. Click the Start button, go to Programs, go to Vidalia, choose Uninstall. This will remove the Vidalia bundle, which includes Tor and Polipo.
  4. Start Firefox. Go to the Tools menu, choose Add-ons. Select Torbutton. Click the Uninstall button.

If you do not follow these steps (for example by trying to uninstall Vidalia, Tor, and Polipo while they are still running), you will need to reboot and manually remove the directory "Program Files\Vidalia Bundle".

For Mac OS X, follow the uninstall directions.


What are these "sig" files on the download page?


Please read the verifying signatures page for details.


Some government or corporate firewalls censor connections to Tor's website. In those cases, you have three options. First, get it from a friend — the Tor Browser Bundle fits nicely on a USB key. Second, find the google cache for the Tor mirrors page and see if any of those copies of our website work for you. Third, you can download Tor via email: log in to your Gmail account and mail ''. If you include the word 'help' in the body of the email, it will reply with instructions. Note that only a few webmail providers are supported, since they need to be able to receive very large attachments.


How do I compile Tor under Windows?

Try following the steps at tor-win32-mingw-creation.txt.

(Note that you don't need to compile Tor yourself in order to use it. Most people just use the packages available on the download page.)




Is there a LiveCD or other bundle that includes Tor?

Yes. Use The Amnesic Incognito Live System or the Tor Browser Bundle.

Why can't I view videos on YouTube and other Flash-based sites?


I'm on OSX or Linux and I want to run another application through the Tor launched by Tor Browser Bundle. How do I predict my Socks port?

Typically Tor listens for Socks connections on port 9050. TBB on OSX and Linux has an experimental feature where Tor listens on random unused ports rather than a fixed port each time. The goal is to avoid conflicting with a "system" Tor install, so you can run a system Tor and TBB at the same time. We're working on a feature where Tor will try the usual ports first and then back off to a random choice if they're already in use. Until then, if you want to configure some other application to use Tor as a Socks proxy, here's a workaround:

In Vidalia, go to Settings->Advanced and uncheck the box that says 'Configure ControlPort automatically'. Click OK and restart TBB. Your Socks port will then be on 9050.

I need an HTTP proxy. Where did Polipo go?

In the past, Tor bundles included an HTTP proxy like Privoxy or Polipo, solely to work around a bug in Firefox that was finally fixed in Firefox 6. Now you don't need a separate HTTP proxy to use Tor, and in fact leaving it out makes you safer because Torbutton has better control over Firefox's interaction with websites.

If you are trying to use some external application with Tor, step zero should be to reread the set of warnings for ways you can screw up. Step one should be to try to use a Socks proxy rather than an http proxy — Tor runs a Socks proxy on port 9050 on Windows, or see above for OSX and Linux.

If that fails, feel free to install privoxy or polipo. You can use our old polipo config file if you like. However, please realize that this approach is not recommended for novice users.

Can I install other Firefox extensions?

Yes. Just install them like normal. But be sure to avoid extensions like Foxyproxy that screw up your proxy settings. Also, avoid privacy-invasive extensions (for example, pretty much anything with the word Toolbar in its name).

Why is NoScript configured to allow JavaScript by default in the Tor Browser Bundle? Isn't that unsafe?

We configure NoScript to allow JavaScript by default in the Tor Browser Bundle because many websites will not work with JavaScript disabled. Most users would give up on Tor entirely if a website they want to use requires JavaScript, because they would not know how to allow a website to use JavaScript (or that enabling JavaScript might make a website work).

I'm an expert! (No, really!) Can I configure NoScript to block JavaScript by default?

You can configure your copies of Tor Browser Bundle however you want to. However, we recommend that even users who know how to use NoScript leave JavaScript enabled if possible, because a website or exit node can easily distinguish users who disable JavaScript from users who use Tor Browser bundle with its default settings (thus users who disable JavaScript are less anonymous).



Unfortunately, Torbutton only works with Firefox right now, and without Torbutton's extensive privacy fixes there are many ways for websites or other attackers to recognize you, track you back to your IP address, and so on. In short, using any browser besides Tor Browser Bundle with Tor is a really bad idea.

We're working with the Chrome team to fix some bugs and missing APIs in Chrome so it will be possible to write a Torbutton for Chrome. No support for any other browser is on the horizon.

I want to leave Tor Browser Bundle running but close the browser.

We're working on a way to make this possible on all platforms. Please be patient.

Google makes me solve a Captcha or tells me I have spyware installed.





Torbutton 1.2.5 (released in mid 2010) detects Google captchas and can automatically redirect you to a more Tor-friendly search engine such as DuckDuckGo, ixquick, or Bing.

Gmail warns me that my account may have been compromised.







Tor installs a text file called torrc that contains configuration instructions for how your Tor program should behave. The default configuration should work fine for most Tor users. Users of Vidalia can make common changes through the Vidalia interface — only advanced users should need to modify their torrc file directly.

Tor Browser Bundle users should edit your torrc through Vidalia. Open the Vidalia Control Panel. Choose Settings. Choose Advanced. Click the button labelled "Edit current torrc". Remember to make sure the checkbox for "Save Settings." is checked. Hit the Ok button and you are done.

Otherwise, you will need to edit the file manually. The location of your torrc file depends on the way you installed Tor:

  • If you installed Tor Browser Bundle, look for Data/Tor/torrc inside your Tor Browser Bundle directory.
  • On Windows, if you installed a Tor bundle with Vidalia, you can find your torrc file in the Start menu under Programs -> Vidalia Bundle -> Tor, or you can find it by hand in \Documents and Settings\username\Application Data\Vidalia\torrc. If you installed Tor without Vidalia, you can find your torrc in the Start menu under Programs -> Tor, or manually in either \Documents and Settings\Application Data\tor\torrc or \Documents and Settings\username\Application Data\tor\torrc.
  • On OS X, if you use Vidalia, edit ~/.vidalia/torrc. Otherwise, open your favorite text editor and load /Library/Tor/torrc.
  • On Unix, if you installed a pre-built package, look for /etc/tor/torrc or /etc/torrc or consult your package's documentation.

If you use Vidalia, be sure to exit both Tor and Vidalia before you edit your torrc file manually. Otherwise Vidalia might overwrite your changes.

Once you've changed your torrc, you will need to restart Tor for the changes to take effect. (For advanced users on OS X and Unix, note that you actually only need to send Tor a HUP signal, not actually restart it.)

For other configuration options you can use, look at the Tor manual page. Remember, all lines beginning with # in torrc are treated as comments and have no effect on Tor's configuration.

How do I set up logging, or see Tor's logs?

If you installed a Tor bundle that includes Vidalia, then Vidalia has a window called "Message Log" that will show you Tor's log messages. Click on "Advanced" to see more details. You can click on "Settings" to change your log verbosity or save the messages to a file. You're all set.

If you're not using Vidalia, you'll have to go find the log files by hand. Here are some likely places for your logs to be:



## else, like one of the below lines.


Log debug file c:/program files/tor/debug.log


I installed Tor but it's not working.

Once you've got the Tor bundle up and running, the first question to ask is whether your Tor client is able to establish a circuit.

If Tor can establish a circuit, the onion icon in Vidalia will turn green (and if you're running Tor Browser Bundle, it will automatically launch a browser for you). You can also check in the Vidalia Control Panel to make sure it says "Connected to the Tor network!" under Status. For those not using Vidalia, check your Tor logs for a line saying that Tor "has successfully opened a circuit. Looks like client functionality is working."

If Tor can't establish a circuit, here are some hints:

  1. Are you sure Tor is running? If you're using Vidalia, you may have to click on the onion and select "Start" to launch Tor.

Tor/Vidalia prompts for a password at start.

Vidalia interacts with the Tor software via Tor's "control port". The control port lets Vidalia receive status updates from Tor, request a new identity, configure Tor's settings, etc. Each time Vidalia starts Tor, Vidalia sets a random password for Tor's control port to prevent other applications from also connecting to the control port and potentially compromising your anonymity.

Usually this process of generating and setting a random control password happens in the background. There are three common situations, though, where Vidalia may prompt you for a password:

  1. You're already running Vidalia and Tor. For example, this situation can happen if you installed the Vidalia bundle and now you're trying to run the Tor Browser Bundle. In that case, you'll need to close the old Vidalia and Tor before you can run this one.
  2. Vidalia crashed, but left Tor running with the last known random password. After you restart Vidalia, it generates a new random password, but Vidalia can't talk to Tor, because the random passwords are different.
    If the dialog that prompts you for a control password has a Reset button, you can click the button and Vidalia will restart Tor with a new random control password.
    If you do not see a Reset button, or if Vidalia is unable to restart Tor for you, you can still fix the problem manually. Simply go into your process or task manager, and terminate the Tor process. Then use Vidalia to restart Tor and all will work again.
  3. You had previously set Tor to run as a Windows NT service. When Tor is set to run as a service, it starts up when the system boots. If you configured Tor to start as a service through Vidalia, a random password was set and saved in Tor. When you reboot, Tor starts up and uses the random password it saved. You login and start up Vidalia. Vidalia attempts to talk to the already running Tor. Vidalia generates a random password, but it is different than the saved password in the Tor service.
    You need to reconfigure Tor to not be a service. See the FAQ entry on running Tor as a Windows NT service for more information on how to remove the Tor service.



EntryNodes $fingerprint,$fingerprint,...
ExitNodes $fingerprint,$fingerprint,...
ExcludeNodes $fingerprint,$fingerprint,...
A list of nodes to never use when building a circuit.
ExcludeExitNodes $fingerprint,$fingerprint,...


The EntryNodes and ExitNodes config options are treated as a request, meaning if the nodes are down or seem slow, Tor will still avoid them. You can make the option mandatory by setting StrictExitNodes 1 or StrictEntryNodes 1 — but if you do, your Tor connections will stop working if all of the nodes you have specified become unreachable. See the Tor status pages for some nodes you might pick.



My firewall only allows a few outgoing ports.

If your firewall works by blocking ports, then you can tell Tor to only use the ports that your firewall permits by adding "FascistFirewall 1" to your torrc configuration file, or by clicking "My firewall only lets me connect to certain ports" in Vidalia's Network Settings window.



  ReachableDirAddresses *:80
  ReachableORAddresses *:443

How stable does my relay need to be?




Great. That's exactly why we implemented exit policies.


The default exit policy allows access to many popular services (e.g. web browsing), but restricts some due to abuse potential (e.g. mail) and some since the Tor network can't handle the load (e.g. default file-sharing ports). You can change your exit policy using Vidalia's "Sharing" tab, or by manually editing your torrc file. If you want to avoid most if not all abuse potential, set it to "reject *:*" (or un-check all the boxes in Vidalia). This setting means that your relay will be used for relaying traffic inside the Tor network, but not for connections to external websites or other services.


Should I be a normal relay or bridge relay?

Bridge relays (or "bridges" for short) are Tor relays that aren't listed in the main Tor directory. That means that even an ISP or government trying to filter connections to the Tor network probably won't be able to block all the bridges.

Being a normal relay vs being a bridge relay is almost the same configuration: it's just a matter of whether your relay is listed publically or not.

Right now, China is the main place in the world that filters connections to the Tor network. So bridges are useful a) for users in China, b) as a backup measure in case the Tor network gets blocked in more places, and c) for people who want an extra layer of security because they're worried somebody will recognize that it's a public Tor relay IP address they're contacting.

So should you run a normal relay or bridge relay? If you have lots of bandwidth, you should definitely run a normal relay — the average bridge doesn't see much load these days. If you're willing to be an exit, you should definitely run a normal relay, since we need more exits. If you can't be an exit and only have a little bit of bandwidth, be a bridge. Thanks for volunteering!

I want to run more than one relay.



    MyFamily $fingerprint1,$fingerprint2,$fingerprint3

where each fingerprint is the 40 character identity fingerprint (without spaces). You can also list them by nickname, but fingerprint is safer. Be sure to prefix the digest strings with a dollar sign ('$') so that the digest is not confused with a nickname in the config file.


Why is my Tor relay using so much memory?


  3. If you're running on Solaris, OpenBSD, NetBSD, or old FreeBSD, Tor is probably forking separate processes rather than using threads. Consider switching to a better operating system.


Why is my Tor relay not named?

We currently use these metrics to determine if your relay should be named:

  • The name is not currently mapped to a different key. Existing mappings are removed after 6 months of inactivity from a relay.
  • The relay must have been around for at least two weeks.
  • No other router may have wanted the same name in the past month.

Can I donate for a relay rather than run my own?

Sure! We recommend two non-profit charities that are happy to turn your donations into better speed and anonymity for the Tor network:

  • is a German charitable non-profit that runs a wide variety of exit relays. They also like donations of bandwidth from ISPs.
  • Noisebridge is a US-based 501(c)(3) non-profit that collects donations and turns them into more exit relay capacity.

These organizations are not the same as The Tor Project, Inc, but we consider that a good thing. They're both run by nice people who are part of the Tor community.


Tell me about all the keys Tor uses.








What are Entry Guards?






You should make every Tor user be a relay.


That said, we do want to encourage Tor users to run relays, so what we really want to do is simplify the process of setting up and maintaining a relay. We've made a lot of progress with easy configuration in the past few years: Vidalia has an easy relay configuration interface, and supports uPnP too. Tor is good at automatically detecting whether it's reachable and how much bandwidth it can offer.







Please help on all of these!

You should transport all IP packets, not just TCP packets.





There are a few reasons we don't:


Doesn't Tor enable criminals to do bad things?


How do I respond to my ISP about my exit relay?
