Home Energy & Utilities Calculators
Size equipment and compare running costs with transparent formulas and defaults you can replace with the numbers on your own bill.
- Generator Size CalculatorAdd up what you need to power in an outage and get running watts, starting watts and a sensible generator size.
- Electricity Cost CalculatorFind what an appliance really costs to run — per day, month and year.
- EV vs Gas Savings CalculatorCompare yearly fuel costs of an EV and a gas car, and how long the price difference takes to pay back.
- Water Heater Cost CalculatorCompare what electric, heat-pump and gas water heaters cost to run each year in your home.
- Solar Panel CalculatorEstimate the solar system size and number of panels to cover your monthly electricity use.
- Air Conditioner BTU CalculatorFind the right room air conditioner size in BTU for your space.
- Pool Volume CalculatorFind how many gallons your pool holds — the number every chemical dose is based on.
- Aquarium Volume CalculatorFind real water volume and weight for a rectangular fish tank.
- Heat Pump vs Furnace Cost CalculatorStart from the gas you already burn for heat and see what a heat pump would cost to deliver the same warmth.
- Trip Fuel Cost CalculatorDistance, MPG and gas price in; gallons, total cost and cost per person out.
- Solar Payback CalculatorA payback estimate that includes rising rates, export credits, degradation, batteries and financing — with every input editable.
- True Electricity Rate CalculatorUse two numbers from your bill to get your real cost per kWh — the figure every energy calculator needs.