Your country is not included? Please visit our global website Language Mass Flow Rate Calculator Do you know the volumetric flow of a gas or gas mixture, but need to express it as mass flow? The KNF Mass Flow Rate Calculator makes it easy. Simply select your gas or gas mixture, enter the volumetric flow rate and our calculator will give you the result. If the gas in your application is at a different temperature or pressure than the one preset in the calculator, you will be able to adjust that as well. Enter your preferred data to calculate your mass flow Gas % The percentage of the total mixture must be 100%. Please check your entries. ¹Expressed as a percentage of mass, not volume or molar share. Add a gas mixture component Pressure Pressure l/min Density² kg/m³ ²Density is calculated dynamically based on gas, pressure and temperature. RESET ALL How to Use the KNF Mass Flow Rate Calculator Volumetric flow is the most common way to represent flow. However, some applications, such as chemical processes, require the actual amount of gas molecules. In these applications, it is much more useful to express the flow as mass flow. KNF has developed this mass flow rate calculator, making it easy to convert volumetric flow rate to mass flow rate. Simply enter the gas or gas mixture to be transferred and its volumetric flow rate. If you know the exact density of your media, you can enter it directly into the KNF Mass Flow Rate Calculator instead of selecting a gas or gas mixture. Then, please also enter the temperature and pressure of the gas in your application. Mass Flow Rate Calculator FAQ Mass Flow Rate Calculator FAQ Why do I need to know which gas I am calculating mass flow for? Each gas has a specific gas constant. The specific gas constant, temperature and pressure can be used to calculate the density of the gas. Therefore, knowing the specific gas constant of the gas is critical to converting from volumetric flow rate to mass flow rate. When do I enter the specific gas constant? This option is intended for gases or gas mixtures with a known specific gas constant and is not listed in our drop-down menu. If the specific gas constant of a gas or a gas mixture is known, entering it into the KNF Mass Flow Rate Calculator is an alternative option to specifying all the components of the mixture. Why are temperature and pressure set at 20 °C (293.15 °K, 68 °F) and 1000 mbar absolute (14.5 psi, 750.06 torr) per default? Temperature and pressure can be freely adjusted to the conditions of the application using the KNF Mass Flow Calculator. The preset values are given in accordance with ISO 8778. These parameters are also used for all gas flow rates given in KNF data sheets. Why does the KNF Mass Flow Rate Calculator offer an option to change the pressure and the temperature? The temperature and the pressure of a gas have a significant impact on its mass and therefore the mass flow. The same volumetric flow rate will result in a higher mass flow rate at lower temperatures and or higher the pressures and vice versa. Is it better to use mass flow rate or volumetric flow rate? This depends on the application. Whenever the mass of a gas is required, it is appropriate to use mass flow. However, if the volume of a gas is the important aspect of an application, it may be more useful to express the flow as a volumetric flow rate. Contact Us Are you looking for a pump and not sure what your mass flow and volumetric flow requirements are? Contact our experts for assistance on these topics. Contact Us Do you want to find out more about our customized pump solutions and service opportunities? Get in touch with our local sales representatives.