How can I conduct an internet speed test?

There are several free tools that provide free internet speed tests.  NextGen Communications recommends the following:  Fast.com and Speedtest.net

Tips for a successful Internet speed test 

• Plug your computer directly into your cable modem. It is necessary to reinitialize the modem (press the Reset button) whenever you change the device connected to it.
• Verify that your computer is not running other tasks. It is important to shut down all applications, navigation windows and tabs. Only the speed test window must be open. Open Task Manager (in Windows), click on the Application tab and then close all the applications.
• Check that only the speed test uses your Internet connection. Open Task Manager (in Windows) and click on the Networking tab to check that the Local Area Connection graph is at zero.