The question comes up often and in this post we clear the confusion.
The quick answer is:
Multiply Mbps by 1000 to get kbps. Conversely divide kbps by 1000 to get Mbps.
Let’s get into the details.
Mbps stands for Megabit-per-second. It is the number of Megabits that are transferred across a communication link. It’s also sometimes referred to as any of the following: data rate, bandwidth, speed or throughput. Similarly kbps stands for kilobits per second.
In the International System of Units (SI) the prefix M stands for mega or 106, while k stands for kilo or 103 (note this is a small k and not capital K which stands for Kelvin).
Therefore 1 Mbit = 103 kbit.
Similarly, 1 Mbps = 103 kbps.
So we can multiply the number of Megabit-per-second by 1000 to get kilobit-per-second. Conversely, divide kbps by 1000 to get Mbps.
Computer file systems use GiB and MiB as storage units. You can see this in your system settings.
However on a specification sheet the same numbers might be referred to as GB and MB, respectively.
GiB stands for Gibibyte, while MiB stands for Mebibyte.
- 1 GiB = 8*10243 bits
- 1 MiB = 8*10242 bits
Note that in this case (unlike with data rate), 1 GiB is not equal to 8*10003 bits and 1 MiB is not equal to 8*10002 bits.
If you want to calculate how long it will take to backup files from your computer over a network connection, it can get quite confusing to switch between units. We designed this File Transfer Calculator that takes the different units into account and simplifies the computation.
Frequently Asked Questions
Can you cite an Autoritative Reference?
NIST provides some historical perspective on the confusion. Essentially “telecommunications engineers use Mbps to mean 106 bit/s”. In other words, when using any networking equipment or technology, 1 Mbps = 1000 kbps. In general multiply by 1000.