Pool Pump Run Time Calculator

Enter your pool volume and pump specs — get turnover time, a recommended daily schedule, and the electricity cost per day and month.

Don't know it? Use the pool volume calculator.

~1,700W for 1.5 HP single-speed; 300–800W for variable-speed at low RPM.

Run time for one turnover
—
Cost per day (one turnover)—
Cost per month—
Cost per season (6 months)—

One turnover per day suits most residential pools; heavy use, heat waves, or algae recovery call for more.

advertisement

The turnover formula

turnover hours = gallons ÷ (GPM × 60)
daily cost = (watts ÷ 1,000) × hours × $/kWh

A "turnover" pushes the pool's full volume through the filter once. Filtration is probabilistic — one turnover actually filters about 60–70% of the water since filtered and unfiltered water mix — which is why sizing matters more than perfection.

A worked example

15,000 gallons through a 50 GPM pump: 15,000 ÷ 3,000 = 5 hours per turnover. A 1,700-watt pump for 5 hours at $0.17/kWh costs $1.45 a day — about $43.50 a month, or $260 over a six-month season.

The variable-speed math that sells itself

Pump power scales with the cube of speed: run at half RPM and you draw roughly one-eighth the power while moving half the water. Doubling the hours at half speed filters the same volume for about a quarter of the cost — run your own numbers above with 400W and 10 hours and compare. It's why utilities offer rebates on variable-speed upgrades.

Frequently asked questions

How long should I run my pool pump each day?

Long enough to turn over the full volume once — typically 6–8 hours in swim season. A 15,000-gallon pool with a 50 GPM pump needs 15,000 ÷ (50 × 60) = 5 hours per turnover.

How much does it cost to run a pool pump?

A 1.5 HP single-speed pump draws roughly 1.6–1.9 kW. Eight hours at $0.17/kWh is about $2.30 a day — $70 a month. Variable-speed pumps running longer at low RPM often cut that by 50–80%.

Is it better to run the pump at night?

Night electricity is cheaper on time-of-use plans, but daytime running fights algae when the sun and swimmers are active. A common compromise: run through the sunniest hours plus a nighttime block for cheap circulation.

How do I find my pump's GPM?

Check the pump label or manual for its flow curve — real-world GPM depends on your plumbing's resistance. A rough field method: note your filter pressure and look up the curve, or use the pump's rated GPM at medium head (most residential systems run 40–60 GPM).

Related calculators

Pool Volume CalculatorHow many gallons your pool holds — the number everything else needs.Pool Chlorine CalculatorExact liquid chlorine dose to hit your target FC level.Pool Salt CalculatorPounds of salt to reach your SWG's target ppm.Pool Shock CalculatorThe right shock dose from your combined chlorine reading.