Free household energy tools
See where your energy money goes.
Turn watts, miles, hours, and utility rates into clear monthly costs—then compare practical ways to save.
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Free home energy calculators
Each calculator shows the formula, assumptions, and a useful cost breakdown. Nothing is uploaded or saved.
Everyday electricity
Appliance cost
Estimate what any household appliance costs to run by day, month, and year using its wattage and your electricity rate.
Calculate nowCooling costs
AC running cost
Estimate the electricity cost of running a window unit, portable AC, mini-split, or central air conditioner.
Calculate nowElectric vehicles
EV charging
Estimate the cost of charging an electric vehicle at home, including charging losses and monthly driving.
Calculate nowLighting savings
LED bulb savings
Compare existing bulbs with LED replacements and estimate annual electricity savings and simple payback.
Calculate nowHot water
Water heater cost
Estimate the monthly and yearly electricity cost of an electric tank water heater from its power and daily runtime.
Calculate nowWhole-home costs
Electricity bill estimator
Estimate monthly and annual electricity charges using your household kWh, provider rate, and fixed monthly charges.
Calculate nowHeating costs
Space heater cost
Estimate what an electric space heater costs per day, active month, and heating season using your own electricity rate.
Calculate nowLaundry costs
Clothes dryer cost
Estimate electricity used per load and the monthly and annual cost of operating an electric clothes dryer.
Calculate nowKitchen energy
Refrigerator cost
Turn the annual kWh on a refrigerator EnergyGuide label into daily, monthly, and yearly electricity costs.
Calculate nowPool equipment
Pool pump cost
Estimate the monthly and annual electricity cost of a pool pump from its measured watts, schedule, and your utility rate.
Calculate nowUnderstand the inputs
Practical energy guides
Use the numbers from your own bill and product labels instead of relying on a national average.
How to find your electricity rate
Locate the useful $/kWh number on a bill—even when the provider lists several different charges.
Read guideHow to read an EnergyGuide label
Find the annual kWh figure, understand the estimated cost, and replace the label's assumed rate with yours.
Read guideWatts, kilowatts, and kWh explained
Learn the difference between power and energy so calculator inputs make sense.
Read guideUse your rate
Enter the electricity price from your latest utility bill.
Check the label
Use the wattage or energy rating printed on your appliance.
Treat it as an estimate
Actual usage changes with settings, weather, condition, and behavior.