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Your Appliances

ItemDaily CostMonthly CostCO2/MoAction
Total Monthly:$0.00
Total Yearly:$0.00
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About

With rising energy prices, understanding the "phantom load" of your household appliances is the first step toward reducing your monthly bill. A gaming PC running 6 hours a day or an old refrigerator with a failing seal can silently add hundreds of dollars to your annual expenses. However, most device labels show Volts and Amps, not the direct cost per hour.

This calculator bridges that gap by converting raw wattage into currency. It includes a comprehensive database of standard appliances - from LED bulbs to HVAC systems - allowing you to stack multiple devices to simulate a full room or house. It also estimates the environmental impact in kilograms of CO2, helping eco-conscious users visualize their carbon footprint.

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Formulas

The formula to calculate the cost C is based on the kilowatt-hour (kWh) usage:

kWh = Watts × Hours1000
Cost = kWh × Rate

For Carbon Dioxide emissions (kg), we use a global average emission factor (approx 0.4 kg/kWh):

CO2 = kWh × 0.4

Reference Data

ApplianceAvg Wattage (W)Cost/Hour (@ $0.15/kWh)Est. Annual Cost (Avg Usage)
Central Air Conditioner3500$0.52$400+
Water Heater (Electric)4500$0.67$500+
Refrigerator150 - 400$0.03$150
Gaming PC (High End)600$0.09$130
LED Light Bulb10$0.001$3
Space Heater1500$0.22High (seasonal)
Washing Machine500 - 1000$0.11$30
Microwave1200$0.18$15

Frequently Asked Questions

Look for a sticker on the back or bottom of the appliance. It will list "W" (Watts). If only Volts (V) and Amps (A) are listed, multiply them (V × A = W) to get the wattage.
No. The rated wattage is the maximum. A fridge cycles on and off; a computer uses less power when browsing than when gaming. This calculator estimates based on "Active" hours.
In the US, the average is ~$0.15/kWh. In Europe, it can range from €0.20 to €0.40/kWh depending on the country and crisis conditions. Check your utility bill for "Supply" and "Delivery" charges combined.
It is an estimate. The carbon intensity of electricity varies by grid (coal vs. solar). We use a standard factor of 0.4kg/kWh, but your local grid might be cleaner or dirtier.