Home Electricity Usage Calculator

Home electricity usage can be estimated by knowing the wattage of your appliances and how many hours per day each one runs.

The formula: kWh = (Watts x Hours per day x Days per month) / 1,000 Monthly cost = kWh x Rate per kWh

Average electricity rate: $0.16/kWh in the US (varies from $0.10 in Louisiana to $0.36 in Hawaii).

Top electricity consumers in a typical home:

• Air conditioning — 3,000–5,000 W, 8 hrs/day in summer = 720–1,200 kWh/month ($115–192)
• Electric water heater — 4,500 W, 3 hrs/day = 405 kWh/month ($65)
• Clothes dryer — 5,000 W, 1 hr/day = 150 kWh/month ($24)
• Refrigerator — 150 W, 24 hrs/day (cycles) = 108 kWh/month ($17)
• Electric oven — 2,500 W, 1 hr/day = 75 kWh/month ($12)
• Dishwasher — 1,800 W, 1 hr/day = 54 kWh/month ($9)
• Washing machine — 500 W, 1 hr/day = 15 kWh/month ($2.40)
• LED TV (55 inch) — 100 W, 5 hrs/day = 15 kWh/month ($2.40)
• LED light bulb — 10 W, 5 hrs/day = 1.5 kWh/month ($0.24)
• Phone charger — 5 W, 3 hrs/day = 0.45 kWh/month ($0.07)

Phantom loads (standby power): Devices that are plugged in but “off” still draw 1–5 watts each. A typical home has 20–40 phantom loads totaling 50–100 watts continuously, adding $5–15/month.

Energy-saving tips:

• Switch to LED bulbs (saves 75% vs incandescent)
• Use a programmable thermostat (saves 10–15% on heating/cooling)
• Run dishwasher and laundry during off-peak hours
• Unplug chargers and devices when not in use
• Air dry clothes when possible (saves $20–30/month)

Tip: Check your actual kWh rate on your electricity bill. It is usually on the first or second page as “price per kWh” or “energy charge.”