Power tools for homeowners
Plain-language calculators that answer the questions you actually have: what is driving my bill, what size generator do I need, and can my panel take one more big appliance.
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Two tools answer most homeowner questions. Both are free and need no account.
Electric Bill Analyzer
Analyze your electric bill to understand usage and find savings.
- ✓ Usage breakdown by category
- ✓ Compare to average homes
- ✓ Time-of-use comparison
- ✓ Personalized saving tips
Home Electrical Load Estimator
Find out how much electrical service your home needs and what size standby generator would cover it.
- ✓ Simplified NEC 220.82 optional method
- ✓ Calculated load in amps
- ✓ Minimum service size
- ✓ Standby generator sizing
More free calculators
Appliance Power
Calculate how much energy your appliances use and what they cost to run.
- Common appliance presets
- Custom power ratings
- Monthly cost estimates
- Energy usage breakdown
EV Charging
Estimate the cost to charge your electric vehicle at home.
- Battery size calculator
- Charge level estimator
- EV vs gas comparison
- Monthly charging costs
Solar Savings
Find out how much you can save with solar panels.
- Panel requirement calculator
- Savings estimates
- ROI calculations
- Sun hours by location
Generator Costs
Calculate fuel costs for whole home generators and compare fuel types.
- Multiple fuel types
- Load level estimates
- Daily & weekly costs
- Fuel type comparison
Common questions
Each one worked through the same verified engine as the calculators, with the inputs and the result shown.
- EV chargingCan a 100 A panel handle an EV charger?Often yes, if the charger is sized to the house. A worked NEC 220.83 calculation on a 1,400 ft² house, gas-heated and then all-electric, shows which Level 2 charger sizes fit a 100 A service.
- GeneratorsWhat size generator do I need for a 2,000 sq ft house?Two honest answers from one NEC calculation: the whole-house standby class and the essentials-only class for a 2,000 ft² gas-furnace home with an electric kitchen, laundry and central air.
- Service sizeHow many amps does a house use?Calculated service current for four typical houses under the NEC 220.82 optional method, from a 1,200 ft² gas home to a 2,600 ft² all-electric one, and why the appliances matter more than the square footage.
- Service size100 A vs 200 A service: which one does my house need?The same 1,600 ft² house calculated three ways under NEC 2023: gas appliances, all-electric, and all-electric with an EV charger. The optional and standard methods both shown, with the minimum service each requires.
- Heat pumpsWill my panel handle a heat pump, or do I need a service upgrade?A 1,900 ft² house on 150 A swaps its gas furnace and air conditioner for a heat pump. The NEC 220.83(B) existing-dwelling calculation, run with 5, 10 and 15 kW of backup strip heat, shows where the service runs out.
- AppliancesElectric water heater vs gas: what does it do to my panel?The same 1,700 ft² house with a gas water heater, a 4,500 W electric tank and a 120 V heat pump water heater, calculated under the NEC 2023 optional and standard methods, with the amps each option adds.