Tor Browser is a web browser based on Mozilla Firefox but configured to protect your privacy.

Tor alone is not enough to protect your anonymity and privacy while browsing the web. All modern web browsers, such as Firefox, support JavaScript, Adobe Flash, cookies, and other services which have been shown to be able to defeat the anonymity provided by the Tor network.

Tor Browser integrates all sorts of security measures to prevent such attacks. But since Tor Browser disables some dangerous functionalities, some sites might not work as usual.

Some frequently asked questions about Tor Browser can be found in the FAQ.

If you want to browse web pages on your local network, refer to our documentation on accessing resources on the local network.

AppArmor confinement

Tor Browser in Tails is confined with AppArmor to protect the system and your data from some types of attacks against Tor Browser. As a consequence, Tor Browser in Tails can only read and write to a limited number of folders.

This is why, for example, you might face Permission denied errors if you try to download files to the Home folder.
  • You can save files from Tor Browser to the Tor Browser folder that is located in the Home folder. The content of this folder will disappear once you shut down Tails.

  • If you want to upload files with Tor Browser, copy them to that folder first.

  • If you have activated the Personal Data persistence feature, then you can also use the Tor Browser folder that is located in the Persistent folder. In that case, the content of this folder is saved and remains available across separate working sessions.

To be able to download files larger than the available RAM, you need to activate the Personal Data persistence feature.

HTTPS encryption with HTTPS Everywhere

Using HTTPS instead of HTTP encrypts your communications while browsing the web.

All the data exchanged between your browser and the server you are visiting is encrypted. HTTPS prevents the Tor exit node from eavesdropping on your communications.

HTTPS also includes mechanisms to authenticate the server you are communicating with. But, those mechanisms can be flawed, as explained on our warning page.

For example, here is how the browser looks when we try to log in to an email account at riseup.net, using their webmail interface:

Notice the padlock icon on the left of the address bar saying "mail.riseup.net". Notice also the address beginning with "https://" (instead of "http://"). These are the indicators that an encrypted connection using HTTPS is being used.

When you are sending or retrieving sensitive information (like passwords), you should try to only use services providing HTTPS. Otherwise, it is very easy for an eavesdropper to steal whatever information you are sending, or to modify the content of a page on its way to your browser.

HTTPS Everywhere is a Firefox extension included in Tor Browser. It is produced as a collaboration between The Tor Project and the Electronic Frontier Foundation. It encrypts your communications with a number of major websites. Many sites on the web offer some limited support for encryption over HTTPS, but make it difficult to use. For example, they might default to unencrypted HTTP, or fill encrypted pages with links that go back to the unencrypted site. The HTTPS Everywhere extension fixes these problems by rewriting all requests to these sites to HTTPS.

To learn more about HTTPS Everywhere, you can see:

Proteção contra JavaScript perigoso

Having all JavaScript disabled by default would disable a lot of harmless and possibly useful JavaScript, and might render many websites unusable.

That is why JavaScript is enabled by default in Tor Browser.

But, we rely on Torbutton to disable all potentially dangerous JavaScript.

We consider this as a necessary compromise between security and usability. As of today we are not aware of any JavaScript that would compromise the anonymity provided by Tails.

To understand better the behavior of Tor Browser, for example, regarding JavaScript and cookies, you can refer to the Tor Browser design document.

Security slider

You can use the security slider of Tor Browser to disable browser features as a trade-off between security and usability. For example, you can use the security slider to disable JavaScript completely.

The security slider is set to Standard by default which gives the most usable experience.

To change the value of the security slider, click on the button on the left of the address bar and choose Security Settings…

Security slider in its default value (low)

Tor circuit

Click on the Show site information button in the address bar to show the Tor circuit that is used to connect to the website in the current tab, its 3 relays, their IP addresses, and countries.

The last relay in the circuit, the one immediately above the destination website, is the exit relay. Its country might influence how the website behaves.

Click on the New Circuit for this Site button to use a different circuit.

You can use Onion Circuits to get more detailed information about the circuits being used.

New Identity feature

The New Identity feature of Tor Browser:

  • Closes all open tabs.
  • Clears the session state including cache, history, and cookies (except the cookies protected by the Cookie Protections feature).
  • Closes all existing web connections and creates new Tor circuits.
  • Erases the content of the clipboard.

To switch to a new identity, click on the button on the left of the address bar and choose New Identity.

This feature is not enough to strongly separate contextual identities in the context of Tails, as the connections outside of Tor Browser are not restarted.

Restart Tails instead.

For more details, see the design and implementation of the Tor Browser.

Use o NoScript para ter ainda mais controle sobre JavaScript

Tor Browser includes the NoScript extension to allow more control over JavaScript, for example, to disable JavaScript completely on some websites.

By default, NoScript is disabled and some JavaScript is allowed by Tor Browser, as explained above.

For more information, you can refer to the NoScript website and features.