A megabit is 106 or 1,000,000 bits.
One megabit (abbreviated "Mb") is equal to 1,000 kilobits. There are 1,000 megabits in a gigabit. It is important to distinguish megabits (Mb) from megabytes (MB), as there are 8 megabits in a single megabyte.
Megabits are commonly used to measure high-speed, or "broadband" Internet connections. For example, an ISP may offer cable modem Internet access with download speeds up to 60 megabits per second (Mbps) and upload speeds up to 10 Mbps. In some parts of the world, fiber connections provide even faster speeds. For example, 100/100 Internet connections are common in Sweden. This type of connection provides symmetrical downstream and upstream data transfers at up to 100 megabits per second both ways.
While megabits are used to measure Internet speeds, megabytes are commonly used to measure file size. This difference makes it a bit tricky to determine how long a download will take. You must first divide the download speed by eight in order to convert megabits per second to megabytes per second. For example, if you download a 100 megabyte file at a speed of 40 Mbps, it will take 20 seconds. (40 Mbps / 8 = 5 MBps. 100 MB / 5 MBps = 20 seconds.)
Updated: October 3, 2013