Garden Hose Flow Rate Calculator
Calculate the water flow rate from your garden hose based on diameter, length, and water pressure.
Flow Rate
Garden hose flow rate depends on hose diameter, length, and water pressure.
Flow rate decreases with longer hoses and smaller diameters due to friction loss.
Typical flow rates at 40 PSI:
| Diameter | 25 ft | 50 ft | 100 ft | 150 ft |
|---|---|---|---|---|
| 1/2" | 9 GPM | 6 GPM | 4 GPM | 3 GPM |
| 5/8" | 17 GPM | 12 GPM | 8 GPM | 6 GPM |
| 3/4" | 27 GPM | 19 GPM | 13 GPM | 10 GPM |
Common residential water pressure: 40–60 PSI
Flow rate uses:
- Filling a 5-gallon bucket: shows you actual GPM (time it!)
- Drip irrigation: needs only 1–4 GPM
- Sprinkler: needs 4–10 GPM
- Pressure washer: needs 2–4 GPM at higher PSI
Hose diameter recommendation:
- 1/2" — light watering, small gardens
- 5/8" — most common, general purpose
- 3/4" — large gardens, long runs, maximum flow