Helping protect your identity while browsing online

What is FoxTor? | Download | Getting Started | Troubleshooting | FAQ

What is FoxTor?
When you use the Internet, you leave a trail of information that can be used to track your online activities. FoxTor is a tool that helps prevent this. It provides an easy and convenient way to browse the Web anonymously using the Firefox web browser.

Foxtor uses the "Masked" and "Unmasked" metaphor to help you control when websites can and cannot track you. Once installed, you Mask and Unmask yourself by clicking the icon in the bottom left corner of your web browser.

Foxtor also enables privacy preferences within Firefox and automatically configures the browser to use Tor and Privoxy. Tor provides users with a free and secure way to communicate anonymously over the Internet. Privoxy ensures that all browser communication passes through the Tor network. Together, these tools ensure that you remain anonymous when browsing online.

Below, you can download a Windows installation program that bundles the necessary software. We also provide just the Firefox browser extension in case you already have the other components or you want to run Foxtor with another operating system.

Download FoxTor

ComponentDownload SiteNotes
Foxtor Mozilla Extension Just the Firefox Extension. See Release Notes
Vidalia Vidalia Website Vidalia = Tor + Privoxy + User Interface. These components provide
the underlying encrypted and anonymous channel and are required for Foxtor.

FoxTor is beta software and should not be used for absolute anonymity.
FoxTor is compatible with any operating system that runs Firefox version 1.5+ and 2.0.

Getting Started

Design Overview: Read this to learn more about FoxTor.

1) The Unmasked state. An icon and descriptive text appear in the Firefox status bar. No Firefox preferences are changed. You connect to the internet as you normally would.
2) Left-Click the icon to Put on your mask and browse anonymously. While an anonymous path is being established you will see the following image:
3) The Masked state. Once the anonymous path has been established, privacy preferences in Firefox are now enabled. Also, the IP address as you appear to destination web servers is shown. Click the icon again to revert to the Unmasked state.
4)Various error message may appear as shown below. See the Troubleshooting section for more information.

5) Right-clicking the text displays this menu:
6) Selecting More Information displays a dialog window where you can retrieve the likely city and country of the originating IP address.


The following are problems that may result because an anonymous web connection could not be verified. See the table below for problem resolution.
Privoxy is not runningStart the Privoxy application and look for the following system tray icon:
Vidalia (and Tor) are not runningIf you are using Vidalia, look for the following system tray icon: . Otherwise, start the Tor software manually.
You appear to originate from the same IP address while Masked and Unmasked. This can happen if your proxy settings for Masked and Unmasked states are the same.Reset your Masked and Unmasked Firefox preferences. 1) Right-click the extension text, select "More Information", 2) select the "Advanced Settings" tab, and press both Reset buttons. This will restore the original (default) firefox preferences.
An Unknown ErrorThe Tor network, itself, may not be responding.Try stopping and restarting Vidalia (or your Tor software). If the problem persists, wait a few moments and try again.

Then click the FoxTor icon again to Put on your Mask.

I tried installing the extension and it still doesn't work. Help!
Well that's weird. See the contact information at the bottom of the page. Send me a note letting me know exactly what you've tried doing and the behavior you're seeing (i.e. does the extension appear?, does it change when you click it? etc.) Please also send any Firefox javascript errors (see Tools->Javascript Console)


How does FoxTor know that I'm masked?
FoxTor makes 2 requests to
Vidalia servers, once using your regular Firefox network connection, and once using Privoxy/Tor. IP addresses are returned and compared. If these IP addresses are different, we have reasonable belief that you are using the Tor network and therefore Masked. Please do not use FoxTor if you believe this is a risk to your privacy.

I see a Privoxy window, what is that about?
This window (see below) appears when Privoxy loads. It is one of the programs that FoxTor relies on to ensure anonymous browsing. You can disregard the window by just minimizing it.

How do I know I am anonymous?
Once the Masked icon appears in the Firefox status bar, you are now browsing anonymously. You can test this yourself by comparing your Masked and Unmasked IP addresses by visiting a site such as

Why do web pages load more slowly when I am Masked?
When you are Masked, your web requests pass through a number of servers around the world. This is the nature of the Tor network and is unavoidable.

What are Vidalia, Tor and Privoxy and why do I care about them?
FoxTor requires Tor and Privoxy to protect your identity. Tor is the underlying software that provides anonymous communication across the Internet. Privoxy passes all web requests from Firefox to Tor. Vidalia is an application that nicely bundles Tor and Privoxy together. When these applications are running, their icons are displayed in the system tray. (Phew, that's confusing, isn't it? :)

Exactly what preferences are changed when I become Masked?
The following preferences are changed:
HistoryZero days
Save Form InformationNo
Save PasswordsNo
Download Manager HistoryDelete upon successful download
CookiesNo cookies are set
Disk CacheZero bytes
Block Pop Up WindowsYes
Allow websites to install softwareNo
Load ImagesFrom originating site only
Enable JavaNo
Enable JavascriptNo
Software UpdatesDisabled
Proxy SettingsConfigured to use Privoxy

What if I want different preferences when I am Masked?
Your in luck, FoxTor already does this. When you switch between being Unmasked and Masked , FoxTor will preserve your Unmasked Firefox preferences and configure a preferences that better protect your identity. When you revert back, your original preferences are restored.

Why did you build this?
FoxTor was developed in response to the Tor GUI Design Contest. Phase 1 involved designing a better GUI and was completed February of 2006. Phase 2 challenged contestants to implement that design in code.
CUPS Phase 1 Entry: Phase 1 ended in early 2006 and this is our complete design document.
CUPS Phase 2 Entry: Phase 2 will end on May 31, 2006 and this is our submission.

Where can I get the code?
Code for the extension is already provided. Just rename "xpi" to "zip" and unzip it.

FoxTor is licensed under the opensource license agreement as specified by the Tor Design Contest Guidelines.

Who built FoxTor and who can I contact for more information?
FoxTor was designed and developed by members of Carnegie Mellon's Usable Privacy and Security Laboratory (CUPS). Please contact Sasha Romanosky (sromanos at cmu . edu) with bug reports, suggestions, or for more information about FoxTor.

What is FoxTor? | Download | Getting Started | Troubleshooting | FAQ