Calculator guide
Convert volumetric flow among milliliters per second, liters per minute, liters per second, cubic meters per second, US gallons per minute and cubic feet per minute. The selector offers these six rates only.
Formula or method
Output = input × source factor ÷ destination factor, using m³/s as the common reference. The gallon option is specifically the US liquid gallon: 1 US gal = 3.785411784 L, so 1 US gpm = 3.785411784 L/min.
How to use this calculator
- Enter a value. The initial amount is 1; the converter also accepts signed finite values.
- Choose From unit and To unit. Available choices are mL/s, L/min, L/s, m³/s, US gpm and cubic feet per minute (cfm).
- Read Converted value with the destination unit. The result changes units, not the underlying volumetric flow.
Worked example
Select US gallon per minute (gpm) → liter per minute (L/min), then enter 1: 1 × 3.785411784 = 3.785411784 L/min. As another check, 100 mL/s × 0.06 = 6 L/min.
Understanding the result
The six supported units are mL/s, L/min, L/s, m³/s, US gpm and cfm. In L/min, one unit of each is respectively 0.06, 1, 60, 60,000, 3.785411784 and 28.316846592. The gallon is US liquid, not Imperial or US dry.
Limitations and assumptions
- This converts volumetric flow only. It does not calculate pipe sizing, velocity, pressure loss, pump selection, fluid properties or a system design.
- The two customary options are US gallon per minute and cubic foot per minute; Imperial gallons and other flow units are not offered. Keep the US convention explicit when comparing results.
- Factors are applied to the entered value without adding measurement precision; displayed results are rounded to at most eight fractional digits.
Frequently asked questions
Is gpm a US or Imperial gallon?
The control explicitly means US gallon per minute. It is not an Imperial gallon or a US dry gallon.
Does this size a pipe or pump?
No. It converts a volumetric rate only and does not model pressure, fluid properties, pipe dimensions or equipment.
Why may a reference table differ in its last digits?
NIST tables can display rounded factors. The US liquid gallon is exactly 3.785411784 L; comparisons should use the same convention and precision.
Sources
Educational and planning information only. Sources are attributed background or formula references, not endorsements. Verify consequential decisions with an appropriate qualified professional.