Electrical • Solar • Battery • Power

Electrical calculators that get to the answer fast.

Use practical calculators for amps, watts, kVA, voltage drop, wire size, batteries, solar, motors, protection and more.

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Calculate three-phase real power from line voltage, line current and power factor.

Calculate AC real power for single-phase or three-phase loads.

Convert amp-hours to watt-hours.

Convert line current to apparent power in kVA.

Convert electrical current to kilowatts.

Convert current and voltage to apparent power in VA.

Calculate voltage from current and resistance.

Convert current in amps to real power in watts.

Estimate an individual appliance’s energy use and running cost.

Estimate backup time from battery bank voltage, amp-hours, usable depth of discharge and efficiency.

Estimate required battery capacity in amp-hours for a load and desired runtime.

Estimate battery charging time from capacity, charge current and charging efficiency.

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