kilogram/second [kg/s] Unit Converter

Definition of kilogram/second [kg/s] unit

Kilogram per second (kg/s) is the SI derived unit of mass flow rate, expressing how much mass passes a specified point, surface, or system each second. One kilogram per second means that one kilogram is transferred during every second.

History of kilogram/second [kg/s] unit

The kilogram per second emerged from the development of the International System of Units (SI), adopted internationally in 1960. It combines the kilogram, the SI base unit of mass, with the second, the SI base unit of time, to express mass transported or processed over time. Although mass-flow measurements existed earlier in industrial engineering, the coherent SI framework standardized kg/s across science and technology. The kilogram’s definition has evolved from a platinum-iridium prototype to a value based on the Planck constant in 2019, while the second is defined using cesium-133 transitions.

Applications of kilogram/second [kg/s] unit

Today, kg/s is used to specify mass flow in pipelines, chemical reactors, fuel systems, and industrial production lines. It describes water, oil, gas, steam, or powdered materials moving through equipment. Engineers use it to size pumps, valves, and process systems, while environmental scientists apply it to quantify emissions, river transport, and atmospheric or oceanic material movement.

Complete list of kilogram/second [kg/s] unit conversion