Electrical & Solar Calculators
Vendor-neutral tools for watts, amps, batteries, wiring, costs, and off-grid solar sizing.
Flagship tool
Off-Grid Solar & Battery Sizing
Full DIY system sizing: load list, battery bank, solar array, inverter, and AU STC rebate.
Battery
Battery Runtime Calculator
How long will your battery run a given load?
Open calculatorBattery Capacity Calculator
Size Ah and Wh from load, hours, and days of autonomy.
Open calculatorBattery Charging Time Calculator
Hours and days to recharge from solar panel output.
Open calculatorBattery Bank Calculator
Series/parallel bank voltage, Ah, and Wh.
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Electrical
Watts to Amps Calculator
Convert watts to amps for AC or DC circuits with optional power factor.
Open calculatorAmps to Watts Calculator
Convert amps to watts at your system voltage.
Open calculatorOhm's Law Calculator
Solve for voltage, current, resistance, or power when you know two values.
Open calculatorPower Factor Calculator
Find power factor and reactive power from real and apparent power.
Open calculatorVoltage Drop Calculator
DC voltage drop for solar wiring by AWG and length.
Open calculatorWire Size Calculator
Pick AWG for ampacity and max voltage drop.
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Cost & billing
Appliance Running Cost Calculator
Estimate daily, monthly, and yearly electricity cost for any appliance.
Open calculatorElectricity Bill Calculator
Estimate your bill from kWh usage with tiered rates and fixed charges.
Open calculatorEV Charging Cost Calculator
Estimate session cost from battery size and state of charge.
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