Flow Rate Converter
Convert between litres per second, litres per minute, cubic metres per hour and US gallons per minute.
Formula and sources updated · Data sources · 1View algorithm, constants and default inputs (JSON)
1 US gal/min = 3.785411784 L/min
About this calculator
Flow rate units mix metric and imperial measures of both volume and time, which makes them easy to misread. Pumps, taps and pipework are usually specified in one of these four.
Worked example
calculated with the default values below
Value 1 · From Litres per minute · To US gallons per minute · Decimal places 4 Result 0.2642 · Litres per minute 1.0000 L/min · US gallons per minute 0.2642 gpm · Cubic metres per hour 0.060000 m³/h
Method and assumptions
Formula basis and scope
Convert volumetric flow via cubic metres per second.
Only the displayed unit definitions are converted; rounding and measurement uncertainty are separate.
Data sources
Disclaimer
These calculators give general conversion results. Rounding and the precision of the value you enter both affect the output, so treat displayed decimals as indicative rather than exact.
Implementation source
This record describes the implementation used by this page. It is not independent validation. External references, when available, support only the stated formula or definition; estimates and custom rules retain their own assumptions.
Formula and variables
Q = x × kf ÷ kt
- x
- entered flow value
- kf
- source-unit factor to L/min
- kt
- target-unit factor to L/min
- Q
- converted flow
All factors convert to L/min. Uses US gallons: 1 US gal = 3.785411784 L and 1 day = 1,440 min, so 1 gpd = 0.0026287583 L/min. Negative flow inputs are rejected.
Frequently asked questions
Why does the converter list gallons per day as a unit?
Gallons per day (gpd) is useful for slow flows such as irrigation and well output. The conversion uses US gallons: 1 gpm = 3.785411784 L/min and 1 gpd = 3.785411784 ÷ 1,440 = 0.0026287583 L/min. This is a unit conversion, not a pump-capacity recommendation.