Want to know which devices drive your power bill? Add your appliances, set your electricity rate and see the running cost per day, month and year. Presets for common devices make it quick to get started.
Electricity Cost Calculator
Add your appliances to see what they cost to run per day, month and year.
Electricity cost FAQ
How do I calculate the cost of running an appliance?
Multiply the appliance watts by the hours used, divide by 1,000 to get kilowatt-hours, then multiply by your price per kWh. For example, a 100 W device used for 10 hours uses 1 kWh.
Where can I find my appliance wattage?
Look for a label or sticker on the back or bottom of the device, or in the manual. A plug-in power meter gives the most accurate real-world reading.
Do devices use power when switched off?
Many devices draw a small standby power when plugged in, often a few watts each. Across a whole home, standby loads can add up, so unplugging or using a switched power strip for idle electronics can save money.
Why is my real bill different from this estimate?
Bills can include fixed daily charges, delivery fees, taxes and tiered or time-of-use rates. Appliances like fridges and air conditioners also cycle on and off, so their real average draw changes with the weather.
The formula behind the calculator
Cost = (watts × hours per day ÷ 1,000) × price per kWh. The result is multiplied by 30.4 days for a monthly figure and 365 for a yearly figure.
How to find the wattage of a device
- Check the rating label on the back or bottom of the appliance.
- Look in the manual or on the manufacturer page.
- Use a plug-in power meter for the most accurate real-world reading.
If a label shows volts and amps instead, multiply them to get watts.
Ways to lower your bill
- Switch heating and cooling devices off or down when you leave the room.
- Replace old bulbs with LEDs.
- Unplug idle electronics or use a switched power strip.
- Run washing machines with full loads on cooler cycles.
- Ask your provider about time-of-use rates if you can shift usage to off-peak hours.
The default rates are approximate averages and change often. Always replace them with the rate printed on your own bill for the best result.