Free Tool · 2026

Off-Grid Solar Sizing Calculator

Estimate the panel wattage, battery capacity, and inverter size you need. Based on standard solar engineering formulas. No email required.

Built by the Luxe Box Properties Editorial Team · Figures sourced below

Step 1 of 3

How much daily energy will you use?

Minimal / Weekend Cabin~1 kWh/day — lights, phone charging, small fridge

Moderate / Efficient Tiny Home~3 kWh/day — LED lighting, laptop, efficient fridge

Full-Time Off-Grid Home~7 kWh/day — full appliances, well pump, some AC/heat

Heavy Use / Homestead~12 kWh/day — multiple buildings, workshop tools

Step 2 of 3

How much sun does your land get?

Lower Sun (Pacific NW, Northeast)~3.5 peak sun hours

Moderate Sun (Mid-Atlantic, Midwest)~4.5 peak sun hours

High Sun (Southwest, Southern CA)~6 peak sun hours

Step 3 of 3

What battery type are you planning?

Lithium (LiFePO4)80% usable capacity, longer lifespan

Lead-Acid / AGM50% usable capacity, lower upfront cost

Recommended System Size

1,200W panels

Sized to your daily usage and location

This is a planning estimate only, using standard off-grid sizing formulas (panel wattage = daily Wh ÷ peak sun hours ÷ 0.75 derate factor; battery capacity = daily Wh × 2 days autonomy ÷ depth of discharge). Actual needs vary by appliance efficiency, climate, and system losses. Always consult a licensed solar installer before purchasing equipment. See our full utility planning guide for cost ranges.

See Off-Grid Solar Resources