Data Speed and Size Calculation

Usually, data connection speeds are measured in bits (and its multiples) and file sizes are measured in bytes (and its multiples).

Bits and Bytes
The bit is the smallest unit of information. A bit can have only two different values, commonly called "0" and "1".

With 4 bits, there are only 16 different possible values (remember that 24 = 16):

One byte is a set of 8 bits. Thus, a byte can have only 256 different values (remember that 28 = 256).

Two examples of calculations follow:

Multiples
In most units, multiples are in powers of 10. For example, 1 kilometer = 1,000 meters (note that 1,000 = 103).

But for binary data, multiples are in powers of 2. For example, 1 megabyte = 1,024 kilobytes (note that 1,024 = 210).

On the table below, the byte multiples are listed with their absolute values in bytes:

The abbreviations of bit multiples are just like the abbreviations of byte multiples of the table above, but with lowercase B instead. Example: megabit &rarr; Mb.

Also from the table above, note that each unit times 1,024 is equal to the next larger unit. A simpler table can be written as below:

Some examples of calculations:

Media Sizes
Follows a table with the most common media and their approximate capacities:

The table above can be used with simple Mathematics concepts to plan how many media is needed to backup data:

Online Calculators
There are multiple calculators of bandwidth and file transfers on the internet. Some are linked below:

https://coderstoolbox.net/network/bandwidth.php

https://techinternets.com/copy_calc

https://www.calculator.net/bandwidth-calculator.html

https://www.expedient.com/file-transfer-time-calculator/

Reference

 * Computer Hope - How much is 1 byte, kilobyte, megabyte, gigabyte, etc.?