Pool Pump Run Time Calculator
How many hours a day to run a pool pump for the turnovers you want, or the flow needed for a set run time.
Result
6.25 hEstimate
Arithmetic from your flow and turnovers; a dirty filter lowers the flow, so the real time is longer.
- Time for one turnover
- 6.25 h (375 min)Estimate
https://calcgallery.com/home-systems/pool-pump-run-time-calculator/
Results are estimates for planning only. Actual needs vary with site conditions, products and workmanship. Always confirm quantities with your supplier and follow local building codes and manufacturer instructions. Read the full disclaimer
How to use the Pool Pump Run Time Calculator
- Enter the pool volume, from the pool volume calculator if you do not know it.
- Choose whether to work out the run time or the flow you need.
- Enter the pump's actual flow, or the hours you want it to run, and the turnovers a day.
- Add the pump's power under More options to see the energy it uses each day.
How it is calculated
run time = pool volume × turnovers ÷ pump flowflow = pool volume × turnovers ÷ hours you want it to runturnover = pool volume ÷ pump flowenergy = pump power × hours runThe units cancel cleanly: gallons divided by gallons per minute gives minutes, and litres by litres per minute likewise. The page converts every combination, so a volume in litres and a flow in cubic metres an hour work too.
Getting the flow right
The run time is only as good as the flow entered. A single-speed pump’s real flow depends on the whole system, so read it from a flow meter or from the pump’s curve at your system’s pressure. Variable-speed pumps often display their flow at each speed. Filtration, not the run time, is what keeps water clear, and sanitising is a separate job; this page does neither.
With your numbers
- Run time = 15,000 gal × 1 ÷ 40 gpm = 6.25 h
Quick reference
Arithmetic from your flow and turnovers; a dirty filter lowers the flow, so the real time is longer.
| Job | Result |
|---|---|
| 15,000 gal at 40 gpm, one turnover | Run time a day: 6.25 h |
| 15,000 gal at 30 gpm | Run time a day: 8.33 h |
| 20,000 gal at 50 gpm | Run time a day: 6.67 h |
| 25,000 gal, two turnovers at 60 gpm | Run time a day: 13.89 h |
| Flow for 20,000 gal in 8 hours | Flow needed: 41.7 gpm |
| Variable speed 15,000 gal at 20 gpm | Run time a day: 12.5 h |
| 50,000 L at 150 L/min | Run time a day: 5.56 h |
| Flow for 60,000 L in 10 hours | Flow needed: 100 L/min |
Common questions about the Pool Pump Run Time Calculator
- How long should I run my pool pump each day?
- Long enough to pass the pool’s whole volume through the filter as many times as you want, usually at least once a day. Divide the volume by the flow actually going through the filter for one turnover, and multiply by the turnovers you want. Local health rules, heavy use, heat and debris can call for more; check what applies to your pool.
- What is a pool turnover?
- The time it takes to circulate a volume of water equal to the pool’s volume. The U.S. Department of Energy’s Building America Solution Center describes one turnover every 24 hours as the minimum filtration for a residential pool, and notes that the pump should be able to turn the pool over within 12 hours.
- Should I run a variable-speed pump longer at a lower speed?
- That is the approach the same Solution Center guide describes: run it slower and run it longer. At half the flow the run time doubles, so the saving depends on the power the pump draws at each speed. Enter that power under More options for each speed and compare the energy per day.
- Why does my pump not reach the flow on its box?
- The box shows the most a pump can move with almost nothing in its way. Filters, pipes, fittings and heaters resist the flow, and the pump settles where its curve meets that resistance. A flow meter, or the flow a variable-speed pump displays, is the figure to enter; a filter that needs cleaning lowers it further.