Electricity Calculator
Calculate the cost of electricity for any appliance. Estimate daily, monthly, and yearly energy usage based on power consumption and your local kWh rate.
How to Calculate Electricity Cost
Understanding your energy bill starts with knowing how much power your devices use and how long they run.
Step 1: Find the Wattage
Most appliances have a label on the back or bottom listing the power consumption in Watts (W). If only Amps (A) are listed, multiply Amps by Volts (usually 120V in US) to get Watts (W = A × V).
Step 2: Calculate kWh
Electricity is billed in Kilowatt-Hours (kWh). To find this, divide the Watts by 1,000 to get Kilowatts, then multiply by the hours used.
kWh = (Watts / 1000) × Hours
Step 3: Multiply by Rate
Check your utility bill for your rate per kWh (often between $0.10 and $0.30). Multiply your total kWh by this rate to find the cost.
Cost = kWh × Rate
Typical Power Usage
- Refrigerator: 100-200 watts (average)
- TV (LED): 60-150 watts
- Gaming PC: 300-600 watts
- Space Heater: 1500 watts
- Central AC: 3000-5000 watts
? Frequently Asked Questions
Look at your most recent utility bill. Divide the total 'Generation' and 'Delivery' charges by the total kWh used. In the US, the average is roughly $0.16 per kWh.
Many devices draw power even when turned off (standby mode). This is called phantom load or vampire power. Unplugging devices like TVs and chargers can save money.
Not always. Heaters, ACs, and fridges cycle on and off. For these, estimate the 'active' running hours per day, or divide the wattage by 2 or 3 for a rough average over 24 hours.