Binary Prefixes Converter

Convert between binary units and decimal units

Computers store data in bits. One bit is either on (1) or off (0). Eight bits make a byte (FF or 256 different values). But this is where things get interesting. What's a kilobyte? Kilo- is the prefix for one thousand. So, a kilobyte would be 1,000 bytes. However, in a computer, there are 1,024 (210) bytes in a kilobyte. This might be just a difference of 24 bytes, but gigabytes are either 1,0003 bytes or 1,0243 bytes. That's a difference of 73,741,824 bytes or about 73 megabytes. If you bought a 100 GB hard drive, you just lost about 7% of the storage, because the computer counts by 1,024, and the manufacturer counts by 1,000.

To remedy this, the IEC created new prefixes specfically for binary units, using so-called binary prefixes. The new units include the kibibyte, mebibyte, and so on. A kibibyte is 1,024 bytes, while an actual kilobyte is 1,000 bytes. For a lengthier exploration of the topic, along with where to use which kind of units, check out Wikipedia's article on binary prefixes.

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