Pool Pump Run-Time Calculator

Run the pump long enough to turn the water over at least once a day — many techs aim for one to two turnovers. Turnover time = pool volume ÷ (flow rate in GPM × 60). For a 15,000-gallon pool with a 60 GPM pump, one turnover takes about 4.2 hours, so two turnovers means roughly 8.3 hours of run time. This calculator works it out from your volume and flow rate.

Turnover time is how long the pump takes to circulate a volume of water equal to the entire pool through the filter. It's calculated as volume ÷ (flow rate × 60 minutes). A shorter turnover means faster filtration and better chemical distribution. Most residential pools are designed for an 8-hour or shorter turnover.

Flow rate (in gallons per minute) depends on the pump's horsepower, the plumbing size, and the system's resistance. The most accurate way is to read it from a flow meter on the return line, or estimate it from the pump curve in your pump's manual at your system's total dynamic head. Typical residential flow rates fall between 40 and 80 GPM.

Run at least part of the cycle during daylight, when sunlight drives chlorine demand and algae growth — circulating then keeps sanitizer distributed when the pool needs it most. Many techs split the run time or use a variable-speed pump running longer at low speed, which moves the same water more efficiently and cheaply. The total daily turnover target stays the same.

No — circulation itself doesn't consume sanitizer, and good turnover actually helps chemicals work efficiently by distributing them evenly and pushing water through the filter. The main cost of longer run time is electricity, which is where variable-speed pumps save money by moving water slowly over more hours.