Gallon per minute is the measurement of how fast water flows, often used when describing the performance of a pump or showerhead. The unit of measure is GPM and can be either a US liquid gallon or a UK imperial gallon, both equal to about 3.78541 liters. This calculator will allow you to convert a value from one of those units to the other, or even between other volume flow rate measurements, such as cubic meters per second (m3/s).
The simplest way to find your GPM is to get a container that holds a full gallon and time how long it takes for the container to fill up completely. Then divide that number by 60, which is the number of minutes in an hour. So if it took 10 seconds for the bucket to fill, your GPM would be 12 (60 divided by 10).
Another method of finding your GPM is to use a pressure tank or other type of container with a known capacity. Record how many seconds it takes to fill up the container, then divide that by the capacity of the container to find your GPM. So if it takes 14 seconds to fill up a five-gallon container, your GPM would be 21.4 (1 / 14 x 5).
Our GPM calculator will allow you to input a volume of water in the first field and choose your unit of time. Then simply enter the number in the Flow rate field, and the calculator will automatically convert your entry from the chosen GPM unit to a corresponding LPM unit. gallons per minute to litres per minute