Pool Pump Run Time Calculator
Find daily pump run hours from pool volume, pump flow rate, and target turnovers per day — shows GPH, one-turnover time, and the substituted math. No login.
How this is calculated
Run time comes from how fast the pump moves water versus how much water the pool holds. Flow is given in gallons per minute (GPM), so the first step is converting it to gallons per hour: GPH = GPM × 60. Dividing the pool's gallons by that GPH gives the time for one full turnover — every drop passing the filter once. Multiply by your target turnovers per day for the recommended daily run hours.
gph = gpm × 60
oneTurnoverHrs = volumeGal / gph (= volumeGal / (gpm × 60))
runHoursPerDay = oneTurnoverHrs × turnovers/day
dimensions mode: volumeGal = pool-volume engine (shape × avg depth × 7.48 gal/ft³)
avgDepth = (shallow + deep) / 2 (deep blank ⇒ shallow) Watch the units. Dividing gallons by GPM alone gives
minutes, not hours — off by 60×. We always convert to GPH first
and echo it (e.g. 40 GPM × 60 = 2,400 GPH) so you can
sanity-check the math. In From dimensions mode the gallons
come from the same engine the Pool Volume Calculator uses (7.48 gal/ft³;
primary-source-validated shape constants), not a rule-of-thumb multiplier.
The result assumes the flow rate you enter. A variable-speed pump run slower moves fewer GPM for longer — enter its effective flow, not its nameplate maximum. This is an advisory planning figure, not a health-code compliance number; turnover targets vary with bather load, debris, and local code.
Sources: Doheny's — Calculate Pool Pump Run Time; Aiper — How to Calculate Pool Pump Run Time; PoolChemicalCalculator — Pool Pump Run-Time / turnover targets.
Sources
- Calculate Pool Pump Run Time. Doheny's. Retrieved .
- How to Calculate Pool Pump Run Time. Aiper. Retrieved .
- Pool Pump Run Time / Turnover Targets. PoolChemicalCalculator. Retrieved .