Electrical and solar calculators
Voltage drop, wire sizing, solar and running costs. Every calculator on this page returns a purchase ready quantity with the waste allowance shown and the working visible.
Voltage Drop Calculator
Calculate voltage drop over a wire run in copper or aluminium, check it against the 3 percent guideline, and see the smallest.
Open calculator →Solar Panel Calculator
Estimate the solar system size and panel count your home needs from your monthly electricity use, your peak sun hours and real.
Open calculator →Electricity Cost Calculator
Work out what any appliance costs to run per hour, day, month and year from its wattage, your hours of use and your rate per kWh.
Open calculator →