KB, MB, GHz, and All of That Stuff

by techtiptom

Originally posted on WIBC.com on 09/10/2009:

In case you haven’t noticed (fat chance), the computer biz is filled with words that start with “kilo” and “mega”, and abbreviations like “K” and “M” and “G”.

These words and abbreviations don’t represent “things”. Rather, they represent numbers. Kind of like the old gangster movies where a bad guy would say fifty g’s rather than fifty thousand dollars. Computer nerds use a different slang for numbers. But the idea is the same.

K. M, and G are Numbers

Let’s start with just the numbers — the K and M and G part. We’ll talk about the “B” and “Hz” and stuff in a moment. See what the abbreviations mean, how they’re often spoken, the approximate number each represents, and the way-too-trivial-a-difference-to-worry-about actual number each represents:

Abbreviation Stands for Spoken as Approximate # Actual #
K Kilo kay or killa 1,000 (a thousand) 1,024
M Mega meg 1,000,000 (a million) 1,048,576
G Giga gig or giga 1,000,000,000 (a billion) 1,073,741,824

If you ignore the boring “actual” numbers, you’ll see there’s a simple pattern to it. Each time you go to from K to M to G, you stick another ,000 onto the end of the preceding number (also known as multiplying the previous number by a thousand), as you can see below:

*1,000 K (kilo)
*1,000,000 M (mega)
*1,000,000,000 G (giga)

So “K” means “thousand” or “,000”, and “M” means “million” or “,000,000” and G means “billion” or “,000,000,000”. Though maybe I should just shut up now before I make it sound more complicated than it is. Suffice it to say if you’re gonna buy a used car, and it has 80K miles on it, then that means the car has 80,000 miles on it. If the car has 20M or 20G miles on it, don’t buy it.