Electrical conversion calculators.
Watts, amps, kVA, Ohm's law, voltage drop, battery capacity — the fast, accurate conversions. Every one also tells you the NEC wire and breaker the result needs, not just the number.
Power & Current
Watts ↔ Amps
Convert watts to amps (or amps to watts) for DC, single-phase, and three-phase — plus the NEC wire and breaker the result needs.
Open converterkW ↔ Amps
Convert kilowatts to amps (or amps to kW) for DC, single-phase, and three-phase circuits, with the matching NEC wire and breaker size.
Open converterkVA → Amps
Convert kVA to amps (full-load current) for single- and three-phase systems — and the breaker and wire to feed it. For transformers and generators.
Open converterCircuit Design
Ohm's Law
Solve volts, amps, ohms, and watts from any two values using the full Ohm's law power wheel — with the wire ampacity for the resulting current.
Open converterVoltage Drop
Calculate voltage drop and percentage over a wire run, and get the smallest wire gauge that keeps you under the NEC 3% recommendation.
Open converter