kWh Cost Calculator
Enter a number of kilowatt-hours and your electricity rate to see what that energy costs. Mark the figure as daily usage to also project a monthly and yearly bill.
How to calculate the cost of electricity
- Enter the amount of energy in kilowatt-hours (kWh).
- Enter your electricity rate per kWh from your bill.
- Tick daily usage if the kWh figure is what you use each day.
- Read the cost, plus monthly and yearly totals when usage is daily.
Examples
30 kWh used in a day
30 kWh, $0.15/kWh, daily usage on
$4.50 today, about $136.88 per month, $1,642.50 per year
Frequently asked questions
How do I work out the cost of a kWh?
Multiply the number of kWh by your rate per kWh. At $0.15 per kWh, 30 kWh costs 30 x 0.15 = $4.50.
What is a kilowatt-hour?
A kilowatt-hour is one kilowatt of power used for one hour. A 1000 watt heater run for one hour uses exactly 1 kWh.
How are the monthly and yearly totals found?
When you mark the kWh as daily, yearly is that daily cost times 365 and monthly is the yearly total divided by 12.
How many kWh does a home use per day?
A typical home uses roughly 20 to 30 kWh per day, though it varies widely with size, climate, heating and appliances.
Why is my bill higher than this estimate?
Bills can add fixed charges, taxes, tiered rates and time of use pricing. This tool covers the energy charge at one flat rate.
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