Before You Get Started
Firefox is entirely free software. You do not have to pay anything to download and install it.
Taking advantage of its popularity, some sites have recently appeared on the Web that attempt to charge money for the download, installation, or support services of Firefox. Such sites are not authorized by the Mozilla Foundation and may misuse personal information that you give to them. If you spot one of these sites, or hear about someone being charged for Firefox, please report it at http://www.mozilla.com/legal/fraud-report/index.html. If you can include the actual address of the site where the download was offered or the site where you submitted your credit card, that helps in tracking down the bad guys. Your credit card records might also list details about the business or name of the company charging your account. This kind of information helps the Mozilla team investigate for trademark and fraud violations and get bad sites shut down.
The official and free download of Firefox can be found at http://getfirefox.com or http://mozilla.com. Free support for Firefox can be found at http://support.mozilla.com. These are the sites you should use for downloading or getting continued support for Firefox.