How to download and install Firefox on Windows
- Visit this Firefox download page in any browser, such as Microsoft Internet Explorer or Microsoft Edge.
- Click the Download Nowbutton. The Firefox Installer that downloads will automatically offer you the best available version of Firefox for your computer.
- If you use Microsoft Edge or Internet Explorer, a notification bar will appear at the bottom of the page with an option to open or run the Firefox Installer file.
- Click Open file on Microsoft Edge or Run on Internet Explorer, to start the process.
- In other browsers, you may need to first save the Firefox installer to your computer, then open the file you downloaded.
Note: If you see an Open File - Security Warning dialog, click Open or Run. 
- The User Account Control dialog may open, to ask you to allow the Firefox Installer to make changes to your computer. If this dialog appears, click Yesto start the installation.
- Wait for Firefox to finish installing.
- When the installation is complete, Firefox will open.
Double-click the Firefox icon that was placed on the desktop whenever you want to go online.
How to download and install Firefox on Mac
Installing Firefox on Mac
To download and install Firefox:
- Visit the Firefox download page in any browser (for example, Safari). It will automatically detect the platform and language on your computer and recommend the best version of Firefox for you.
- Click Download Firefox.
- Note: If you want to have a choice of the language for your Firefox installation, click the Download options and other languages link instead.
- Once the download has completed, the file (Firefox.dmg) may open by itself and pop open a Finder window containing the Firefox application. Drag the Firefox icon on top of the Applications folder in order to copy it there.
- Note: If you do not see this window, open the Firefox.dmg file that you downloaded.
- After dragging Firefox to the Applications folder, hold down the control key while clicking in the window and select Eject "Firefox"from the menu.
Tip: You can add Firefox to your dock for easy access. Just open your Applications folder and drag Firefox to the dock.
Firefox is now ready for use. Just click on its icon in the dock or Applications folder to start it.
Starting Firefox for the first time
When you first start up Firefox, you will be warned that you downloaded Firefox from the Internet. Because you download Firefox from the official site, click Open.
Upon installation, Firefox will not be your default browser, which you'll be notified about. That means that when you open a link in your mail application, an Internet shortcut, or HTML document, it will not open in Firefox. If you want Firefox to do those things, click Use Firefox as my default browser. If you're just trying out Firefox or simply do not wish to set Firefox as your default browser, click Not now.
