🚰 Gallons Per Minute Calculator (GPM)
Calculate flow rate in gallons per minute (GPM) from a measured volume and time, useful for pumps, wells, and plumbing fixtures.
What This Calculator Does
Gallons per minute (GPM) is the standard way to describe flow rate for pumps, wells, faucets, and irrigation systems. This calculator finds GPM from a simple bucket test: how much water you collected and how long it took.
The Formula
Flow rate is GPM = volume collected (gallons) / time taken (minutes). Since time is often easier to measure in seconds with a stopwatch, this calculator converts seconds to minutes automatically by dividing by 60 before doing the division.
This bucket-test method is a common, practical way to check a well pump’s output, a shower head’s flow, or a hose’s fill rate. For consistent results, use a container of known volume and time the fill with a stopwatch over at least 10-15 seconds to reduce measurement error.