Electricity Cost Calculator
Find what an appliance costs to run per day, month and year from its wattage and your electricity price.
Electrical Tools
Ohm's law, power, voltage drop, wire gauges, resistor colour codes, LED resistors and electricity cost.
LED Resistor Calculator
Find the series resistor for one or more LEDs, with the nearest standard value and power rating.
Ohm's Law Calculator
Find voltage, current, resistance or power from any two of them with Ohm's law.
Resistor Color Code Calculator
Read 4-, 5- and 6-band resistor colour codes as a value, tolerance and temperature coefficient.
Voltage Drop Calculator
Calculate the voltage drop along a copper or aluminium cable for single- or three-phase circuits.
Watts, Amps and Volts Converter
Convert between watts, amps and volts for DC, single-phase and three-phase AC, with power factor.
Wire Gauge Converter (AWG to mm²)
Convert AWG wire sizes to diameter and mm², with resistance per kilometre and a metric size table.