About WattGauge

WattGauge is a free collection of solar calculators built for RV owners, off-grid cabin builders, and homeowners going solar. Every calculation runs in your browser — no account, no login, no data sent anywhere.

The tools cover the most common sizing and estimation tasks: panel and battery sizing, off-grid system design, home savings estimates, payback analysis, and EV charging with solar.

Sizing calculators use widely accepted formulas and NREL peak sun hour data. Financial calculations follow standard methodology for IRR, NPV, and LCOE. All results are estimates suitable for planning and budgeting — not a substitute for a professional site assessment or licensed installer quote.

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