kilobyte

computer science

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Last updated

July 21, 2026

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A kilobyte (KB) is a unit of digital information storage. While the prefix "kilo" typically means 1,000, in computer science, a kilobyte traditionally represents 1,024 bytes. This is because computer memory is based on powers of two, and 1,024 is 2¹⁰, the closest power of two to 1,000.1

A byte is the fundamental unit of computer information, consisting of 8 binary digits (bits). Bytes are the smallest units of storage that a computer can operate on and can represent a single character or a number. While historically kilobyte meant 1,024 bytes, the computer industry has largely adopted decimal prefixes, meaning a kilobyte can also refer to 1,000 bytes in some contexts.2

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byte
…in binary digits, originally one kilobyte was not 1,000 bytes but 1,024 bytes (1,024 = 2¹⁰), and thus one megabyte (MB) was 1,024 × 1,024 bytes and so on. However, with some notable exceptions such as the Microsoft Windows operating system, the computer industry has switched over to decimal prefixes,…
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…in binary digits, originally one kilobyte was not 1,000 bytes but 1,024 bytes (1,024 = 2¹⁰), and thus one megabyte (MB) was 1,024 × 1,024 bytes and so on. However, with some notable exceptions such as the Microsoft Windows operating system, the computer industry has switched over to decimal prefixes,…
Read More