zeroprefix

Zeroprefix is a formatting convention in which numeric values are represented with one or more leading zeros to reach a fixed width. The term is sometimes used interchangeably with zero-padding or leading zeros. In many programming and data-handling contexts, zeroprefixing helps produce uniform strings for sorting, alignment, and identifiers.

Common applications include serial numbers, file names, timestamps, and database fields that require fixed-length text. For example, numbers 9 and 42 might be represented as 0009 and 0042 to maintain a constant width. This enables correct lexicographic ordering and predictable display in tabular formats.

Implementation typically involves left-padding the numeric string with zeros to reach a specified width. Most programming languages offer padding facilities, such as string formatting functions, printf-like formatting, or dedicated pad utilities. Potential issues include the historical risk that leading zeros could be interpreted as octal literals in some languages, and the fact that numeric types do not preserve leading zeros when converted back from text. When leading zeros must be preserved, it is common to handle the value as a string or to store the zeroprefixed representation separately.

See also: zero-padding, leading zeros, fixed-width formatting, lexicographic order, serial number formatting.