Calculators
Pick the calculator that matches the home-energy question you're trying to answer. Every tool gives you an instant result and explains the calculation — no email required and nothing collected.
- ElectricityEnergy Bill CalculatorWhat could my electricity cost me over a year, and what could efficiency upgrades trim?Estimated annual costPossible yearly savingsOpen calculator
- SolarSolar Savings CalculatorHow big a system would I need, and how long before it pays for itself?Estimated system sizePossible yearly savingsPayback and net costOpen calculator
- HeatingHeat Pump ROI CalculatorWould a heat pump cost me less to run than the furnace or boiler I already have?Estimated net install costAnnual running-cost differencePayback, when there is oneOpen calculator
- Smart homeSmart Home Cost CalculatorWhat would these devices cost up front, and which could help reduce energy use?Estimated upfront costPossible yearly savingsRough paybackOpen calculator
Not sure which one to use?
- Your bill went up and you don't know whyStart with the Energy Bill Calculator, then read the causes ranked by cost. Open the Energy Bill Calculator
- You have an installer's quote in front of youSanity-check it against the Solar or Heat Pump calculator before you sign anything. Open the Heat Pump ROI Calculator
- You're deciding what to buy firstThe Smart Home Cost Calculator ranks devices by what they cost against what they save. Open the Smart Home Cost Calculator
How TrimWatt estimates results
Every figure on these pages is an estimate, not a quote. Each calculator states the assumptions it works from and the limits of what it can see, and shows the sources behind its default figures. Your actual costs and savings will vary with your home, your rates and your habits.