kilogram [kg] Unit Converter

Definition of kilogram [kg] unit

The kilogram is the SI base unit of mass. Since 2019, it has been defined by fixing the numerical value of the Planck constant, providing a universal realization through quantum and physical measurement methods rather than a material artifact.

History of kilogram [kg] unit

The kilogram originated in the metric system developed in revolutionary France during the 1790s, where it was intended to represent the mass of one liter of water at its maximum density. In 1889, the General Conference on Weights and Measures adopted an international prototype made from platinum and iridium. For more than a century, this artifact defined the unit. In 2019, scientists replaced the artifact-based definition by fixing Planck’s constant, linking the kilogram to fundamental physics and enabling reproducible measurements worldwide.

Applications of kilogram [kg] unit

The kilogram is used worldwide to measure mass in science, industry, commerce, and everyday life. It supports weighing food, luggage, medical doses, and manufactured goods. Laboratories use it to calibrate balances and realize precise measurements, while engineering and physics apply kilograms in force, energy, and material calculations. Common multiples include grams and tonnes.

Complete list of kilogram [kg] unit conversion