💡 Appliance Energy Cost Calculator
Enter an appliance's power, how many hours a day it runs and your electricity rate to see the running cost.
Per day
1.08
3.6 kWh
Per month
32.87
Per year
394.47
1,315 kWh
Cost = power (kW) × hours × rate. Find the watts on the appliance's label or a plug-in energy meter; for things that cycle (fridges, heaters, AC) use the average hours they actually run, not the hours they're plugged in. Amounts are in whatever currency you enter. 🔒 In your browser.
How the appliance energy cost calculator works
Running cost is energy used times price. The tool converts the appliance's watts to kilowatts, multiplies by the hours it runs each day for the daily kilowatt-hours, then multiplies by your electricity rate — and scales the result to a month and a year so you can see the real yearly cost of leaving something on.
Find the wattage on the appliance's rating label or measure it with a plug-in energy meter. For anything that cycles or is thermostat-controlled — fridges, freezers, heaters, air conditioning — use the average hours it actually runs, not the hours it's switched on, or you'll overestimate. Standby power adds up too; a device "off" but plugged in can still draw a few watts.
Frequently asked questions
How do I calculate the running cost of an appliance?
Cost = power (kW) × hours used × electricity rate. A 150 W fridge running an effective 8 hours a day at $0.30/kWh costs about $0.36 a day, or roughly $130 a year.
How much does it cost to run something 24/7?
Watts ÷ 1000 × 24 × 365 × your rate. A 10 W device left on all year at $0.30/kWh costs about $26; a 100 W one about $263. Small always-on loads add up over a year.
Where do I find an appliance's wattage?
On its rating label or in the manual, or measure it directly with an inexpensive plug-in energy monitor — which also captures cycling and standby draw more accurately than the nameplate figure.
What is standby power?
The energy a device uses while "off" but still plugged in — a few watts for TVs, chargers, consoles and anything with a remote or clock. Individually small, collectively a noticeable share of a home's bill; a switched power strip eliminates it.
How can I cut an appliance's running cost?
Run it less, replace it with a more efficient model (LED lighting, a modern fridge), and cut standby draw. This tool shows the yearly cost, which makes it easy to see when a more efficient replacement pays for itself.