Water Heater Energy Cost Calculator

Estimate water heater operating cost for electric, natural gas, propane, and tankless water heaters. Calculate daily cost, monthly cost, annual cost, kWh use, therm use, propane use, BTU demand, and cost per gallon of hot water.

Calculate Water Heater Energy Cost

Energy Needed = Gallons × 8.34 × Temperature Rise ÷ Efficiency.
Your result will appear here.

How the water heater energy cost calculator works

Cost by hot water use:
The calculator estimates heat energy needed from daily hot water use and temperature rise.

Energy use estimate:
The calculator converts BTU demand into kWh, therms, and propane gallons.

Cost by heater rating:
The calculator estimates electric cost from heater wattage and run time.

Savings comparison:
The calculator compares current monthly cost to an estimated cost using a new efficiency or fuel rate.

Why use a water heater energy cost calculator?

A water heater energy cost calculator helps estimate how much it costs to heat water each day, month, and year.

It can help compare electric cost, gas cost, propane cost, efficiency, standby loss, temperature rise, daily hot water use, and possible savings.

What your result means

Your result shows estimated water heater energy use and operating cost. This is a planning estimate only. Actual cost depends on utility rates, heater efficiency, tank losses, water temperature, usage habits, pipe losses, fixture flow rates, and seasonal incoming water temperature changes.

Water heater energy cost formulas

Frequently asked questions

How do you estimate water heater energy cost?

Estimate the heat needed to raise water from incoming temperature to hot water temperature, adjust for heater efficiency, then multiply the energy use by your utility rate.

Does a higher temperature setting cost more?

Yes. A higher hot water temperature increases temperature rise, which increases the energy needed to heat the water.

Why does efficiency matter?

Efficiency affects how much purchased energy is converted into useful hot water. Lower efficiency means more energy is needed for the same amount of hot water.

Is this water heater energy cost calculator exact?

No. This calculator gives a planning estimate. Actual costs depend on utility rates, water use, heater condition, standby losses, and seasonal water temperature changes.