Toasters have a wattage range from 800 to 1400. To calculate the cost of electricity, the toaster's wattage must be multiplied by the number of hours it is used per day, then by the number of days it is used per year.

The final calculation in determining the electrical cost of a toaster is to multiple the above product by the local cost of electricity per kilowatt hour. For example, if a toaster is used six minutes a day for 300 days a year, the initial calculation is 0.1 x 300 = 30. The product of 30 is then multiplied by the cost of kilowatt hours, which the DOE estimates at 11 cents per kWh as of August 2014. At that cost, it would cost $3.30 to run a toaster over the course of a year.