6 tools
Power calculators
Power conversions look trivial until alternating current is involved. These tools ask which kind of system you have, so a three-phase or low power-factor load is not quietly treated as if it were DC.
Power and current conversions
Move between watts, volts and amps for DC, single-phase and three-phase systems.
Watts to Amps Calculator
Current depends on more than watts and volts. Pick your system type so the calculation uses the right relationship — power factor for AC, and √3 for three-phase.
Amps to Watts Calculator
Convert current to real power using the relationship for your electrical system. AC results keep power factor and apparent power visible.
kW to Amps Calculator
Convert real kilowatts to current without confusing kW with kVA. Choose DC, single-phase or balanced three-phase and enter the correct voltage and power factor.
kVA to Amps Calculator
Convert apparent power to current for single-phase or balanced three-phase systems. Because kVA already includes voltage and current, power factor is not applied to the current formula.
Three-phase systems
Calculate balanced line current while keeping line voltage, real power, apparent power, power factor and motor efficiency distinct.
Three-Phase Current Calculator
Calculate balanced three-phase line current while stating whether your power figure is electrical input kW, motor mechanical output kW or apparent kVA.
Energy use and cost
Turn appliance power, duty cycle and standby draw into kWh and a user-supplied tariff cost.
Appliance Energy Cost Calculator
Estimate energy and cost for appliances that run continuously, cycle on and off, or consume standby power. Enter your own all-in energy rate and comparison period.
Methodology
How these tools are built
Every calculator here shows the formula it uses, the assumptions behind it and the limits of the model. Where a figure is a typical published value rather than a specification, it says so and lets you change it.