Mbps vs MB/s: What’s the big deal?

At one point or another of our lives, we’ve all received the infamous calls from an ISP sales rep claiming that their Internet is “100 mega”, and thus blazing fast. But to those who aren’t used to the terminology, these words mean very little, if anything. Or, you may have a 20 megs connection, but your download speed is nowhere near 20 megabyte per second. Does that mean that your ISP scammed you?

Actually, no, for there are two unit of measurement when it comes to transfer speeds. Your computer usually informs you of your download speed in kilobytes or Megabytes per second (kB/s or MB/s), whereas networks reason in kilobits and megabits per second (kbps or Mbps). And here’s the catch: The difference between Mbps and MB/s is that they use a different unit of measurement; bits in the case of Mbps and bytes in the case of MB/s. This has to do with the fact that, in a network transfer, not all bits are actually information that belongs to the file, but is vital to ensure that the communication between the two computers was successful. This is commonly referred to as overhead information and there’s not really much you can do to reduce it, because its existence is vital to the network itself.

But how exactly do megabits and megabytes differ? A bit is the simplest unit of measure of information and it can take two values, either 0 or 1. But the components in our computers, namely the processor, generally perform tasks in bytes, a unit of measurement composed of 8 bits, for a total of 256 possible values. Notice how 256 is a power of 2. Historically, multiples of the byte have always been powers of 2, because this simplified the job of computer engineers and programmers. Thus, a kilobyte is 1024 bytes (the power of 2 closest to 100), and a Megabyte is 1024 kilobytes.

So, we’re stuck with two measures for the foreseeable future, but there’s one trick that you should know. You can easily convert Megabits per second to Megabytes per second by simply dividing it by 8 and the opposite by multiplying by 8. Or, Windows’ calculator has a useful conversion feature. And you can even convert using the Chrome search bar by typing

X megabits to megabyte

where X is the number you want to convert.

About Andrea Luciano Damico 109 Articles
Andrea Luciano Damico is a freelance translator from Italy. Among his interests are linguistics, technology, video games, and generally being a chill guy. He runs Let's Translate.it and Tech4Freelancers.net.