Enter the mass out and the mass accumulated into the Calculator. The calculator will evaluate the Mass Input. 

Mass Input Formula

MI = MO + MA


  • MI is the Mass Input (kg)
  • MO (kg) is the mass out
  • MA (kg) is the mass accumulated

To calculate Mass Input, sum the total mass output and the total mass accumulated.

How to Calculate Mass Input?

The following steps outline how to calculate the Mass Input.

  • First, determine the mass out. 
  • Next, determine the mass accumulated. 
  • Next, gather the formula from above = MI = MO + MA.
  • Finally, calculate the Mass Input.
  • After inserting the variables and calculating the result, check your answer with the calculator above.

Example Problem : 

Use the following variables as an example problem to test your knowledge.

mass out = 5

mass accumulated = 4


What is mass flow rate and how is it different from mass input?

Mass flow rate is a measure of the amount of mass moving through a given point per unit time, usually expressed in kilograms per second (kg/s). It differs from mass input in that mass input refers to the total mass entering a system, without necessarily accounting for the time factor involved in its movement.

Can mass input be negative?

In theoretical scenarios, mass input could be considered negative if the system is losing mass. However, in practical terms, mass input typically refers to the mass being added to a system, thus it is generally positive.

Why is understanding mass input important in engineering and physics?

Understanding mass input is crucial in fields like engineering and physics because it helps in the analysis of mass balance within systems. This is essential for the design, optimization, and operation of processes in industries such as chemical engineering, mechanical engineering, and environmental science.

How can errors in measuring mass input affect a system’s operation?

Errors in measuring mass input can lead to incorrect calculations of mass balance, potentially resulting in inefficiencies, safety hazards, or operational failures in systems. Accurate measurement is critical for process control, optimization, and ensuring the safety and efficiency of industrial operations.