kilogrami

Kilogrami is the plural form of the kilogram, the SI base unit of mass. The symbol for the unit is kg, and it is used worldwide in science, industry, and everyday life to measure the amount of matter in an object. The kilogram is one of the seven fundamental SI units and plays a central role in precise mass measurements.

Historically, the kilogram was defined by the International Prototype Kilogram (IPK), a platinum-iridium cylinder kept at the International Bureau of Weights and Measures (BIPM) in Sèvres, France. Copies of the IPK were used for calibration by national metrology laboratories. In 2019, the definition was revised to fix the numerical value of the Planck constant h to exactly 6.62607015×10^-34 joule seconds, thereby defining the kilogram in terms of fundamental physical constants rather than a material artifact. Realization of this definition typically involves precision instruments such as the Kibble balance and methods based on Avogadro’s constant.

One kilogram equals 1000 grams. The gram is a convenient suprametric unit for smaller masses, while the tonne (or metric ton) equals 1000 kilograms. In common conversions, 1 kilogram is approximately 2.20462 pounds avoirdupois. A liter of water at around 4 °C has a mass of about 1 kilogram, illustrating the practical link between volume and mass in everyday contexts.

In usage across languages, the term and its plural forms differ, but the concept remains the standard measure of mass in the metric system, providing a stable foundation for quantitative science and commerce.