# Electricity Cost Calculator

## Using Electricity Consumption Cost Calculator

Find out how much your electricity costs per month. Simply enter your wattage, average daily use, and the cost per kilowatt-hour and find out the monthly cost for the electric usage. This is great if you want to find out how much an electrical device or light bulb costs to power for a month.

## How to Estimate Electricity Cost

Electricity costs can be found by finding the total wattage used, multiplying by the hours used per day and dividing by 1000. This is the kilowatt hours used. To find the price for that usage you simply multiply by the cost per kilowatt hour charged by the electric company. The calculator above can simplify the process, but we’ll go through the formula step by step.

The kilowatt-hour usage formula is: P_{(W)} × T_{(h/day)} / 1000_{(W/kW)}

The total price formula is: Electricity_{(kWh)} × Cost_{(cost/kWh)}

The electricity cost will vary, but the national average electricity cost is $.12 per kilowatt-hour. You can find this cost by looking on your electric bill.

Let’s try an example to understand the formulas. If we have a computer with a 400w power supply, we can find the cost per month to keep the computer running for 4 hours per day. We start with 400w x 4h / 1000, which equals 1.6. The next step is to multiply by the kilowatt per hour cost, 1.6 * .12, which equals $.19 per day. The monthly cost of this requires us to multiply by 30, $.19 x 30 = $5.70. It would cost $5.70 per month to power the average computer for only 4 hours per day.

The most common application of this is calculating lighting costs. This formula can be used to find out how much a light bulb or light fixture costs per month. You can use our lighting cost estimator to find out how much your lights cost to keep on for the month and to find out how much you can save by upgrading to LED light bulbs.