Calculators
Every calculator on GoSolarIndex uses real formulas — shown on the page, not hidden — and real data where a calculation needs it (state electricity rates, production data, published product specs). No signup, and every result is saved to the URL so you can share or bookmark it.
Solar Calculator
System size, installed cost, and payback using your state's real electricity rate and production data.
Solar Panel Count Calculator
Calculate how many panels and how much roof space your home needs using your power bill and state sun hours.
Battery Backup Sizing Calculator
Determine the exact battery kWh capacity and inverter kW output required for whole-home or critical outage backup.
Solar Payback & Net Metering Calculator
Calculate your solar break-even timeline and 25-year ROI factoring utility net metering policies and post-2025 tax rules.
Generator Size Calculator
Pick your appliances, get a recommended generator kW, and see real published models that cover it.
Battery Runtime Calculator
How long a battery or power station can run a given load, accounting for inverter efficiency.
Electricity Cost Calculator
What an appliance costs to run per day, month, and year at your state's real rate.
Watts to Amps Calculator
Convert watts to amps for single-phase or three-phase circuits.
Amp Hours to Watt Hours Calculator
Convert Ah to Wh so you can compare battery capacity across different voltages.