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Mass Flow Rate Converter

Convert mass passing through a surface or conduit per unit time across kg/s, kg/min, kg/h, lb/s, and lb/h with real-time bidirectional calculations and continuity equations.

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Popular Mass Flow Rate Conversion Shortcuts

Instant pair conversions with verified scientific and mathematical formulas

Quick Pairs

kg/s to lb/h→

1 kg/s = 7,936.64 lb/h

lb/h to kg/s→

1,000 lb/h = 0.1260 kg/s

kg/h to lb/h→

1 kg/h = 2.20462 lb/h

lb/h to kg/h→

1 lb/h = 0.45359 kg/h

1 kg/s = 2.20462 lb/s

Mass Flow Rate Reference Equivalents (1 Kilogram per second)

Standard ratios measured against the base Kilogram per second (kg/s)

Reference Table

Unit Name	Symbol	Equivalent in 1 kg/s	Quick Pair Page
Kilogram per second	kg/s	1 kg/s = 1 kg/s	Base Unit
Kilogram per minute	kg/min	1 kg/s = 60 kg/min	kg/s to kg/min →
Kilogram per hour	kg/h	1 kg/s = 3,600 kg/h	kg/s to kg/h →
Pound per second	lb/s	1 kg/s = 2.204623 lb/s	kg/s to lb/s →
Pound per hour	lb/h	1 kg/s = 7,936.641439 lb/h	kg/s to lb/h →

Industrial Mass Flow Rate Benchmark Reference Chart

Engineering mass flow rate lookup table comparing steam boilers, jet fuel burn, chemical pipelines, and municipal water mains

Lookup Matrix

System / Application	kg/s (SI)	kg/h	lb/s	lb/h (Imperial)
Laboratory Dosing Syringe Pump	0.00001 kg/s	0.036 kg/h	0.00002 lb/s	0.079 lb/h
Residential Gas Boiler (Natural Gas)	0.00067 kg/s	2.40 kg/h	0.00147 lb/s	5.29 lb/h
Commercial HVAC Chilled Water Branch	0.25 kg/s	900.0 kg/h	0.551 lb/s	1,984.1 lb/h
Fire Hose Water Stream (2.5 inch)	15.8 kg/s	56,880 kg/h	34.83 lb/s	125,400 lb/h
Boeing 737 Max Cruise Fuel Burn	0.65 kg/s	2,340 kg/h	1.433 lb/s	5,158.8 lb/h
GE90 Commercial Turbofan Takeoff Fuel	2.60 kg/s	9,360 kg/h	5.732 lb/s	20,635 lb/h
Supercritical Steam Turbine (600 MW)	550.0 kg/s	1,980,000 kg/h	1,212.5 lb/s	4,365,150 lb/h
SpaceX Falcon 9 Merlin 1D Engine	275.0 kg/s	990,000 kg/h	606.3 lb/s	2,182,576 lb/h
Saturn V First Stage F-1 Rocket Engine	2,578.0 kg/s	9,280,800 kg/h	5,683.5 lb/s	20,460,654 lb/h

Fluids & Process Engineering Guide

Mass Flow Rate: Fluid Continuity, Flow Meters & Industrial Conversion Standards

A comprehensive engineering guide to mass flow measurement, Coriolis meters, continuity equations, and unit conversions across chemical and propulsion systems.

Mass Continuity & Conservation in Ducts

In fluid dynamics, mass flow rate ṁ represents the time derivative of mass: ṁ = dm / dt. Under the Principle of Mass Conservation, the total mass flowing into a control volume must equal the mass exiting plus the rate of internal accumulation:

ṁ = ∫_A ρ · (v · n̂) dA = ρ · A · v_avg

Mass Flow Rate Equation for Incompressible & Compressible Conduit Flow

When gas accelerates through a converging-diverging rocket nozzle or supersonic steam turbine, the local cross-sectional area and velocity change drastically, but the product ρ·A·v remains constant along the stream tube.

Coriolis vs Differential Pressure Mass Flow Meters

Industrial process plants require precise mass flow instrumentation:

Direct Coriolis Flow Meters

Measure true mass flow directly by vibrating a flow tube and sensing the Coriolis phase shift induced by moving mass. Unaffected by changes in fluid viscosity, temperature, or density.

Inferred Differential Pressure (Orifice / Venturi)

Calculate volumetric flow from pressure drops (Bernoulli's principle) and require simultaneous pressure and temperature sensors to infer fluid density and compute mass flow.

Industrial Applications & Unit Standards

Common measurement standards vary across industries:

Thermal Power Stations & Steam Boilers: Steam output is rated in lb/h (pph - pounds per hour) or metric tons per hour (t/h). A 500 MW utility boiler produces over 3,000,000 lb/h (378 kg/s) of superheated steam.
Aviation Turbofans: Aircraft fuel flow meters display fuel consumption in kg/h (Airbus) or lb/h (Boeing). Cruise fuel consumption for a twin-engine airliner typically ranges between 2,200 and 3,000 kg/h (4,850–6,600 lb/h).
Rocket Propulsion: Liquid rocket engines consume tons of cryogenic oxidizer and propellant per second, requiring ratings in kg/s or lb/s.

About Mass Flow Rate Units & Formulas

Multiply the mass flow by the factor relative to 1 kg/s.

Kilogram per secondkg/s

SI mass flow unit

Kilogram per minutekg/min

Process mass rate

Kilogram per hourkg/h

Industrial boiler and steam flow

Pound per secondlb/s

Imperial propulsion mass rate

Pound per hourlb/h

Aviation fuel flow rate

FREQUENTLY ASKED QUESTIONS

Mass Flow Rate Converter FAQs

Frequently asked questions regarding mass flow rate conversion metrics, formulas, and real-world calculation standards

How do you convert kg/s to lb/h?

To convert kilograms per second (kg/s) to pounds per hour (lb/h), multiply by 7,936.64: lb/h = kg/s × 7,936.6412.

Step-by-Step Derivation:

1 kg = 2.20462262 lb
1 hour = 3,600 seconds
Formula: 2.20462262 × 3,600 = 7,936.6414 lb/h per 1 kg/s.
Reverse Conversion: To convert lb/h to kg/s, divide by 7,936.64 (or multiply by 0.0001260). For instance, 10,000 lb/h ÷ 7,936.64 = 1.2599 kg/s.

What is mass flow rate in fluid mechanics?

Mass flow rate (ṁ, m-dot) is the mass of a substance which passes per unit of time through a given cross-sectional boundary.

SI Base Unit: kilogram per second (kg/s).
Fundamental Equation: ṁ = ρ · A · v, where ρ (rho) is fluid density (kg/m³), A is cross-sectional duct/pipe area (m²), and v is flow velocity (m/s).
Law of Conservation of Mass: In steady-state compressible or incompressible fluid dynamics without nuclear reaction, mass flow rate remains strictly constant along a continuous conduit: ρ₁ · A₁ · v₁ = ρ₂ · A₂ · v₂.

What is the difference between mass flow rate and volume flow rate?

Mass flow rate (ṁ) measures the actual mass moving per second (kg/s or lb/h), which is independent of temperature and pressure variations.

Volume flow rate (Q) measures the spatial volume displaced per second (m³/s, CFM, or GPM). Because gases compress and expand with temperature and pressure, volume flow rate changes continuously through compressors, nozzles, and heaters, whereas mass flow rate remains strictly conserved.

How do you convert volume flow rate to mass flow rate?

To convert volumetric flow rate (Q) to mass flow rate (ṁ), multiply by the fluid's density (ρ):

ṁ = Q · ρ

For liquid water at 20°C (density ≈ 1,000 kg/m³ = 1 kg/L): a volumetric flow of 10 Liters/second yields a mass flow of 10 L/s × 1 kg/L = 10 kg/s (79,366 lb/h).

Why do aerospace and turbine engineers calculate in lb/h or kg/s instead of gallons/hour?

Aero-engines and rocket thrusters produce thrust directly proportional to the momentum change of reactant mass (Thrust = ṁ · v_exhaust). Furthermore, jet fuel expands and contracts substantially with altitude temperature shifts. A gallon of cold jet fuel contains more chemical mass and combustion energy than a warm gallon, making mass flow rate (lb/h or kg/s) the only rigorous thermodynamic metric for fuel metering.