Flow Rate Converter

The Flow Rate Converter changes a volumetric flow rate from one unit into every other supported unit at once.

Enter a value such as a pump rating in litres per minute, an HVAC airflow in cubic feet per minute, or a water-supply figure in cubic metres per hour, and the tool instantly shows the equivalent in all the units engineers and plumbers actually use.

It covers the metric family — cubic metres per second and per hour, litres per second, per minute and per hour, and millilitres per minute — alongside the imperial and US units that cause the most confusion: US gallons and imperial (UK) gallons per minute and per hour, plus cubic feet per minute and per second.

Because US and UK gallons are different volumes, the converter keeps them separate so you never mix up a US gpm pump spec with a UK rating.

Everything pivots through the SI base unit (cubic metres per second) using exact factors, then rounds to a clean number of decimals to avoid floating-point noise.

Negative values are allowed where flow direction matters.

The whole calculation runs locally in your browser — nothing is uploaded or stored — and you can copy the full set of equivalents with a single click for a spec sheet, report or quote.