Sump Pump Runtime Calculator
Estimate sump-pump runtime and electricity cost from inflow volume, pump flow, cycle size, motor power and operating days.
Default project preview
34.3 minutes/day
Runtime per cycle
21 sec
Daily cycles
100
Monthly runtime
17.1 h
Monthly energy
6.39 kWh
Calculator
Build the material order
Your order will appear here
Enter the project details and calculate a rounded material estimate.
Input and output guide
What each value means
The labels and units below are part of this calculator’s visible methodology. Replace every default with measurements or product data from the actual project.
Average water entering sump
Enter this project assumption in gal/day. The current imperial default is 1200 gal/day.
Delivered pump flow
Enter this project assumption in gpm. The current imperial default is 35 gpm.
Water removed per pump cycle
Enter this project assumption in gal. The current imperial default is 12 gal.
Motor input power
Enter this project assumption in hp. The current imperial default is 0.5 hp.
Operating days per month
Enter this project assumption in a unitless value. The current imperial default is 30. Minimum: 0. Maximum: 31.
Electricity rate
Enter this project assumption in per kWh. The current imperial default is 0.18 per kWh. Minimum: 0.
How to read the outputs
Runtime per cycle
cycle volume ÷ delivered flow. Default preview: 21 sec.
Daily cycles
daily inflow ÷ cycle volume. Default preview: 100.
Monthly runtime
30 operating days. Default preview: 17.1 h.
Monthly energy
0.37 kW input. Default preview: 6.39 kWh.
Monthly energy cost
pump motor only. Default preview: $1.15.
Annualized energy cost
twelve equal months. Default preview: $13.81.
Methodology
Transparent calculation
BuildMeter converts every input to a consistent internal unit, applies the selected allowance, and rounds products up to whole purchasable units.
Daily runtime = daily inflow ÷ delivered pump flow. Cycles = inflow ÷ water removed per cycle. Energy = motor input × monthly runtime.
BuildMeter Guides
Understand the measurements and assumptions
Use these visible reference guides before changing project inputs or planning allowances.
FAQ
Sump Pump Runtime Calculator questions
Why does actual flow differ from the pump label?+
Pump curves show flow at different head. Vertical lift, pipe friction and fittings reduce delivered flow.
Is frequent cycling harmful?+
Very short cycles can increase starts and wear. Pit dimensions and switch settings affect cycle volume.
Does this size a backup system?+
No. Backup sizing must consider outage duration, peak inflow, battery condition and alarm strategy.