Understanding your result
Every displayed value represents the same volume passing a point per unit time. US and Imperial gallon outputs are separate because their volumes differ.
To estimate the volume you are filling or draining, use the Tank Volume Calculator .
The formula
A litre is one-thousandth of a cubic metre. Changing the time unit changes the numeric rate as well as changing the volume unit. For example, one litre per second is sixty litres per minute, not one-sixtieth.
Worked example
A flow of 60 L/min equals 1 L/s, 3.6 m³/h, and 0.001 m³/s. One US gallon per minute corresponds to 3.785411784 L/min, while one Imperial gallon per minute corresponds to 4.54609 L/min.
How to use this calculator
- Enter the nonnegative flow value from a meter, specification, or calculation.
- Select both its volume convention and time unit.
- Read the equivalent output matching the units required by your next calculation.
Identify what GPM means
A specification marked only GPM is ambiguous without context. US manufacturers commonly mean US liquid gallons, while another document may use Imperial gallons. Confirm the standard in the documentation before selecting a unit. The converter deliberately avoids a single unlabeled gallon result that could silently introduce a material error.
Flow, pressure, velocity, and mass are different
A volumetric rate does not determine pipe velocity without a cross-sectional area. It also does not determine mass flow without density or pump pressure without a hydraulic model. A constant 60 L/min would fill a geometric 300-litre volume in five minutes, but that simple division assumes the actual flow stays constant throughout filling.
Assumptions & limitations
What this calculation assumes
- The input is volumetric flow at the stated measurement conditions.
What to keep in mind
- No pressure-drop calculation, pump sizing, density conversion, or actual-to-standard gas-volume adjustment.
Common questions
Can I convert kilograms per hour with this tool?
No. That is mass flow. You need fluid density at the relevant conditions to turn it into a volume rate.
Does this convert standard gas flow to actual flow?
No. Standard and actual gas volumes depend on the stated pressure, temperature, and sometimes compressibility. Unit conversion alone cannot resolve those conditions.