Solar System Sizing Calculator
Enter your location and daily energy usage to get a complete system recommendation — panel wattage, battery bank size, inverter, and charge controller.
How to Use These Results
This calculator gives you a starting point for system design. The panel wattage accounts for an 80% derate factor covering real-world losses (temperature, shading, wiring, dust).
Once you know your panel and battery sizing, use our other tools to finish your design:
- Wire Gauge Calculator — size your wiring runs from panels to charge controller and battery bank.
- Battery Bank Calculator — figure out exact series/parallel configuration for your battery bank.
- Cost Estimator — get a ballpark BOM cost and see how much you save going DIY.
New to DIY solar? Read our guide on series vs parallel panel wiring to understand how your wiring configuration affects system voltage and performance. If your panels aren't hitting the numbers you expected, our solar panel troubleshooting guide walks through how to diagnose the issue.