uom

A unit of measure (UOM) is a standardized quantity used to express the amount of a physical attribute, such as length, mass, volume, or count. UOMs enable clear specification, comparison, calculation, and communication of quantities across processes like purchasing, inventory, manufacturing, shipping, and pricing. In data systems, UOMs are typically represented by codes (for example, EA for each, KG for kilogram, L for liter) and linked to conversion rules.

Key concepts include base units and derived units. A base unit is the primary unit used for internal calculations within a given measurement dimension (for length, the meter is a common base unit; for mass, the kilogram). Other units can be related to the base unit through conversion factors—such as 1 meter = 100 centimeters, 1 liter = 1000 milliliters, or 1 dozen = 12 units. Conversions allow quantities to be stored, aggregated, and analyzed consistently across systems that use different UOMs.

Standards and best practices emphasize standardization and clarity. The ISO/IEC 80000 family governs quantities and units, and the International System of Units (SI) defines widely used base units and prefixes. In practice, organizations should maintain a controlled set of UOMs, designate a base UOM per item or product family, implement explicit conversion rules, and ensure consistent UOM labeling to avoid ambiguity and data quality issues.

Common considerations include avoiding ambiguous abbreviations, handling non-integer conversions carefully, and validating UOMs during data exchange to ensure accurate reporting and inventory control.