Mass Flow Rate Converter
Convert mass flow rate between kg/s, kg/h, g/s, lb/s, lb/h, and metric ton/h.
Used in chemical engineering, HVAC, and industrial process design calculations.
Type in any field — the others update instantly.
Mass flow rate measures how much mass passes through a point per unit of time. It is essential in chemical engineering, HVAC, and fluid mechanics.
All conversions use kg/s as the base unit.
Metric conversions:
- 1 kg/s = 1,000 g/s = 3,600 kg/h = 3.6 tonne/h
Imperial conversions:
- 1 kg/s = 2.20462 lb/s = 7,936.64 lb/h
- 1 lb/s = 0.453592 kg/s
Cross-system:
- 1 tonne/h = 2,204.62 lb/h
- 1 lb/h = 0.000126 kg/s
Common applications:
| Application | Typical Flow |
|---|---|
| Household faucet | ~0.1 kg/s |
| Fire hose | ~10 kg/s |
| Industrial boiler | 1–50 tonne/h |
| Gas turbine (air) | 50–500 kg/s |
| Oil pipeline | 100–5000 tonne/h |
The reason engineers track mass flow rather than volume comes down to one fact: mass is conserved, volume isn’t. Heat a gas or drop its pressure and it expands, so a fixed volumetric flow can carry very different amounts of actual material. Mass flow sidesteps that entirely, which is why it’s the unit of choice for combustion, chemical reactions, and anything where the quantity of substance, not the space it fills, is what counts.
That distinction is the usual source of error. A “1,000 m³/h” gas reading represents different masses at different temperatures and pressures, while “1 kg/s” is unambiguous. When a process depends on how much material is actually moving, such as fuel into an engine or reactant into a reactor, mass flow is the figure to trust.
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