Electrical Calculation Guides
Understand the relationships behind common electrical calculations. These guides explain the formulas, units and practical considerations used for power conversion, voltage drop and wire-sizing estimates.
Browse electrical guides
5 practical guides covering Ohm's law, current, voltage, resistance, electrical power, voltage drop and wire size.
Ohm's Law Explained: Voltage, Current and Resistance
Learn how Ohm's Law connects voltage, current and resistance, with formulas, rearrangements and practical calculation examples.
ElectricalWatts, Amps and Volts Explained
Understand watts, amps and volts, how they relate through electrical power formulas, and how to convert between them.
ElectricalHow to Calculate Voltage Drop
Learn what voltage drop is, how conductor resistance and current affect it, and how to estimate voltage drop and percentage drop.
ElectricalHow to Choose Electrical Wire Size
Learn the main factors that affect electrical wire sizing, including current, conductor material, temperature, voltage drop and installation conditions.
ElectricalAmps to Watts and Watts to Amps Conversion Guide
Learn how to convert amps to watts and watts to amps for simple DC and AC calculations, with formulas and examples.
When you are ready to calculate a result, visit our Electrical Calculators for interactive tools related to these guides.