Kilobyte (KB)

Kilobyte (KB)

What Does Kilobyte (KB) Mean?

A kilobyte (KB) is a multiple unit used forbinary data. Although "kilo" generally refers to 1,000, in computerscience, one kilobyte often refers to 1,024 (2^10) bytes. Itmay also be used to refer to 1,000 bytes depending on the context. This measureis often used to describe memory capacity and disk storage.

A bit is thesmallest data measurement unit. A kilobyte is just a convenient way to specifya large number of bits and is equivalent to 8,000 bits under the InternationalSystem of Units (SI) (or 8096 bits for computer programming and ITapplications).


The kilobyte is applied in a variety of measurement contexts, including:

  • RAM or ROM Memory size

  • Processor cache size

  • The amount of storage available     on media such as an SD memory chip or flash drive

  • Hard disk drive storage     capacity

  • An iPhone memory chip     capacity

In 2000, theInstitute of Electrical and Electronics Engineers (IEEE) incorporated theInternational Electrotechnical Commission's (IEC) formal approval of SI metricprefixes. Newly added SI terms included:

  • Kibibyte (KiB) equals 1,024     bytes

  • Mebibyte (MiB) equals     1,048,576 bytes

  • Gibibyte (GiB) equals     1,073,741,824 bytes

These newmeasurements have yet to make an impact in any areas of internationalinformation technology and are rarely used. The difference between the SI andbinary measurements standards for data is approximately 4.86 percent.