Free Solar Tool · 2026

Battery Bank Sizing Calculator

Enter your loads, days of autonomy, and battery specs to get exact capacity, battery count, series/parallel wiring and cost estimate.

Daily Load Profile

Appliance

Watts (W)

Hours/day

Qty

Total daily consumption 0 Wh/day

— or enter daily consumption directly —

Leave blank to use the load table above

Battery & System Settings

Battery Type

System Voltage

Battery Voltage (V)

Battery Capacity (Ah)

Days of Autonomy

Days without sun/charging

Inverter Efficiency

Temperature Derating

Battery Price (USD each)

Results

Required Bank Capacity

—Ah

Configure loads and click Calculate

Energy Capacity

—kWh

Depth of Discharge

—%

Total Batteries Needed

—batteries

In Series

—

In Parallel

—

Est. Bank Weight

—kg

Est. Bank Cost

—

Recommended Charge Current (0.1C)

—A

Recommended Fuse / BMS Rating

—A

At system voltage — use next standard fuse size up

Calculations use standard DoD and efficiency factors per battery chemistry. Actual results vary with brand, age, and temperature.
Built by DoCrack.me · Free to use · No signup required