A kibibyte is a unit of data storage that equals 2 to the 10th power, or 1,024 bytes.
While a kilobyte can be estimated as 10^3 or 1,000 bytes, a kibibyte is exactly 1,024 bytes. This is to avoid the ambiguity associated with the size of kilobytes. A kibibyte is 1,024 bytes and precedes the mebibyte unit of measurement.
For a list of other units of measurements, view this Help Center article.