Electricity Cost Calculator
Work out how much an appliance or device costs to run. Enter its power in watts or kilowatts, how many hours a day you use it, and your electricity price per kWh, and instantly see the energy it uses and what it costs you per day, week, month, and year. Perfect for sizing up heaters, air conditioners, computers, fridges, and any always-on gadget so you can spot the energy hogs and cut your bill.
ToolsSoup's Electricity Cost Calculator tells you exactly what any appliance costs to run. Enter the device's power in watts or kilowatts, how long you use it each day, and your electricity rate per kWh, and it instantly shows the energy it consumes plus the cost per day, week, month, and year. Use it to compare appliances, find the devices that quietly drive up your bill, and decide whether an upgrade or a usage change is worth it. Everything runs in your browser: no uploads, no sign-up, and your numbers never leave your device.
What is an electricity cost calculator?
An electricity cost calculator estimates how much it costs to run an electrical device based on its power rating, how long it runs, and the price you pay for electricity. Electricity is billed per kilowatt-hour (kWh) — the energy used by a 1,000-watt device running for one hour. By multiplying a device's power (in kilowatts) by the hours it runs and then by your price per kWh, the calculator turns a wattage on a label into real money. It's handy for budgeting, comparing two appliances, deciding whether to leave something on, or working out the payback on a more efficient model.
How to use the electricity cost calculator
Getting an accurate running cost takes just three numbers, and the result updates as you type:
- Enter the device's power and choose watts or kilowatts — you'll usually find this on a label or in the manual.
- Type how many hours a day you actually use it.
- Enter your electricity price per kWh, which you can read off your utility bill.
- Read the energy used and the cost per day, week, month, and year in the results below.
How is the cost of running an appliance calculated?
The cost to run an appliance is its power in kilowatts multiplied by the hours it runs multiplied by your price per kWh. First convert watts to kilowatts by dividing by 1,000 — a 1,500-watt heater is 1.5 kW. Running it 5 hours a day uses 1.5 × 5 = 7.5 kWh per day. At a price of $0.15 per kWh, that's 7.5 × 0.15 = $1.13 a day, about $7.88 a week and roughly $411 a year. This calculator does that math for you and scales the daily figure out to weekly, monthly, and yearly totals.
How can I lower my electricity bill?
Start by finding the biggest energy users: anything that combines high wattage with long run times — heaters, air conditioners, electric water heaters, and old fridges — usually dominates the bill. Cutting daily run time, switching to a more efficient model, or eliminating standby draw on always-on devices makes the most difference. Plug a few appliances into this calculator and compare their yearly cost to decide where your money actually goes and which change pays off fastest.
Why use this electricity cost calculator?
- Accepts power in either watts or kilowatts with a one-click toggle.
- Shows both the energy used (kWh) and the cost per day, week, month, and year.
- Works with any currency — just enter your local price per kWh.
- Updates live as you type with no button to press.
- Runs entirely in your browser — free, no ads, and your numbers never leave your device.
Frequently asked questions
How do I calculate the cost of running an appliance?
Multiply the appliance's power in kilowatts by the hours it runs per day and by your price per kWh. A 1,500 W (1.5 kW) heater used 5 hours a day at $0.15/kWh costs 1.5 × 5 × 0.15 = $1.13 a day. Enter those three numbers above and the calculator does it instantly.
What is a kilowatt-hour (kWh)?
A kilowatt-hour is the amount of energy a 1,000-watt device uses in one hour. It's the unit your electricity is billed in, so the cost of running anything is its energy in kWh multiplied by your price per kWh.
Where do I find my electricity price per kWh?
Check your most recent electricity bill — it lists the rate per kWh (sometimes called the unit price or energy charge). If you have tiered or time-of-use pricing, use an average rate, or run the calculator separately for each rate to compare.
How do I convert watts to kilowatts?
Divide watts by 1,000. A 1,500-watt appliance is 1.5 kilowatts, and a 60-watt bulb is 0.06 kilowatts. You don't have to do this yourself — just enter the wattage and choose Watts, and the calculator converts it for you.
Does this work for any country or currency?
Yes. The calculator is currency-neutral: it multiplies energy by whatever price per kWh you enter, so the cost comes out in your local currency. Just use the rate from your own bill.