Home energy cost calculators
Work out what your appliances cost to run and where your electricity money goes. Every calculator shows its formula, worked examples and the source and date of its data. Results are estimates, not professional calculations.
Electricity Costs
What your appliances, your bill and your kilowatt-hours really cost.
- Find out what an appliance costs to runAppliance electricity costSee what it costs to run any appliance per hour, per month and per year, using your own state electricity price.Open calculator
- Turn kilowatt-hours into dollarskWh to dollars converterTurn kilowatt-hours into dollars, or dollars into kilowatt-hours, at your state average price or your own rate.Open calculator
- Estimate your monthly electric billMonthly electric bill by stateEstimate your electric bill from the kWh you use and your price, and see how it compares with the average home in your state.Open calculator
- See what an electric space heater costs to runElectric space heater costFind out what your space heater costs to run, and what the same heat would cost from a gas furnace or a heat pump.Open calculator
- See what it costs to charge an electric car at homeElectric car charging cost by stateFind out what charging an electric car at home costs where you live, and compare it with a gasoline car if you want to.Open calculator
- Find out what your pool pump costs to runPool pump running costWork out what your pool pump costs to run, and check whether a more efficient pump would pay back its price.Open calculator
Heating and Cooling
Size a system and compare what it costs to run.
- Find the right BTU size for a room air conditionerAC BTU calculatorEnter the size of your room to see the cooling capacity to look for in a window or wall air conditioner.Open calculator
- Compare the running cost of window units and central airWindow AC vs central AC costCompare what room air conditioners and a central system cost to run, and see how long a higher price takes to pay back.Open calculator
- Compare heating a home with a heat pump or a gas furnaceHeat pump vs gas furnace calculatorSee what the same heat costs from a gas furnace and from a heat pump, at your state prices or your own.Open calculator
- Find the right dehumidifier size for a roomDehumidifier sizeEnter your room and how damp it feels to see the capacity ENERGY STAR recommends, then estimate what it costs to run.Open calculator
- Estimate what a smart thermostat could saveSmart thermostat savingsEnter what heating and cooling cost you, and see about what a smart thermostat could save and when it pays for itself.Open calculator
- Compare heating with propane or an electric heat pumpPropane vs electric heating costSee what the same heat costs from a propane furnace and from an electric heat pump at your prices.Open calculator
- Look up the insulation R-value for your climate zoneInsulation R-value by climate zonePick your climate zone and attic to see the R-value ENERGY STAR recommends to add in an existing home.Open calculator
Water, Solar and Backup
Water heaters, solar, batteries and generators.
- Compare the running cost of two water heatersTank vs tankless water heater costSee what two water heaters cost to run in a year for your hot water use, and how long a higher price takes to pay back.Open calculator
- Find how many home batteries you need for backupHome battery sizeWork out how many home batteries cover your home for the number of days you choose, and check that they can carry the load.Open calculator
- Find the generator size you need in an outageGenerator sizeList what you want to power during an outage and see the running and starting watts a generator must deliver.Open calculator
Guides with a calculator built in
Each guide explains one decision and has the calculator for it.
- Heat pump vs gas furnace: which costs less to heat
- How much does it cost to run a mini split
- What size air conditioner do I need
- How much electricity does a central AC use
- Window AC vs central AC cost
- Tankless vs tank water heater cost
- How much does a space heater cost to run
- Electric car vs gas car cost per mile
How we work
Prices come from the U.S. Energy Information Administration and are stored with their source and date. Formulas are shown on each page and are tested against known cases before publishing. Read the methodology and sources.
There are 16 calculators and 8 guides so far. More are added only when they are ready and checked.