GARDEN FIELD BOOK / CALCULATOR 11
Garden Hose Flow Rate Calculator
Measure how much water your hose actually delivers. Catch water in a marked container, time the fill and enter both measurements to calculate GPM, GPH and liters per minute. Add repeat trials if you want to compare results without guessing from hose size or pressure.
2 US gallons collected in 24 seconds
Equivalent to 300 gallons per hour or about 18.93 liters per minute.
MEASURE YOUR WATER FLOW
Enter the bucket test
MEASURED OUTPUT
Your hose flow rate
Calculate a bucket test to see GPM, GPH, L/min and an optional comparison of repeat trials.
Trial-by-trial comparison
| Trial | Volume | Time | GPM |
|---|
The combined result uses total volume divided by total time, not an unweighted average of unequal tests. It describes only the hose setup and faucet setting you measured.
MEASURE ONCE, REPEAT IF NEEDED
How to run a useful hose bucket test
Use a container with an actual measured volume mark, a timer and the hose setup you want to evaluate. Repeat the same arrangement when checking whether the result is stable.
Keep the attachment in place
Attach the nozzle or hose-end equipment you actually expect to use. Set the faucet to the opening you intend to measure. A different nozzle or valve setting can change flow.
Time a known volume
Direct the discharge into a stable container, start the timer with the flow and stop when the water reaches your measured mark. Record gallons or liters and the elapsed seconds or minutes.
Compare real trials
Record up to five separate tests. The overall rate uses combined volume divided by combined time. Individual GPM values remain visible so you can spot large differences.
CALCULATION METHOD
Volume divided by time gives measured flow
Example: 2 US gallons collected in 24 seconds gives 2 × 60 ÷ 24 = 5 GPM. The same measured flow is 300 GPH or about 18.93 L/min. Five gallons collected in 60 seconds gives the same flow. Keeping the time and volume paired prevents misleading comparisons.
This measures flow, not water pressure (PSI). Water pressure cannot be calculated from the bucket result alone.
READ THE RESULT CORRECTLY
One bucket test is not a complete irrigation design
Results depend on the setup
Hose diameter, length, faucet opening, nozzle and other restrictions can change flow. The measured rate applies to the configuration and operating condition tested.
Do not turn GPM into PSI
A pressure gauge and other system information are needed to evaluate pressure. This calculator does not estimate pressure loss, emitter uniformity or sprinkler coverage.
Watch the fill line and timer
A poorly marked bucket, delayed stopwatch or fluctuating supply can skew a short test. Retest under the same conditions if individual results vary noticeably.
GARDEN WATERING GUIDES
Use the measured flow in context
Return to Garden Calculators & Planning Tools to find other measuring and planning tools.