Electricity Cost Calculator
Enter the wattage of an appliance, how many hours per day you use it, and your electricity rate to see what it costs per day, month, and year.
US average ≈ $0.13/kWh; check your bill for your exact rate
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kWh per month
Appliance breakdown
| Appliance | W | h/day | kWh/mo | $/mo |
|---|
How Is Electricity Cost Calculated?
$$\text{kWh} = \frac{\text{Watts} \times \text{Hours}}{1{,}000}$$
$$\text{Cost} = \text{kWh} \times \text{rate}$$
For example: a 100 W light bulb running 5 hours per day uses 0.5 kWh/day. At $0.13/kWh, that costs $0.065/day, or about $1.95/month.
Average US Electricity Rates by State
Electricity rates vary widely. The national average in the US is approximately $0.13–$0.17 per kWh (2024), but rates differ significantly by state and utility:
| State | Approximate rate |
|---|---|
| Louisiana | $0.09/kWh (low) |
| Oklahoma | $0.09/kWh |
| Idaho | $0.10/kWh |
| National average | $0.13–0.17/kWh |
| New York | $0.20/kWh |
| Connecticut | $0.23/kWh |
| California | $0.28/kWh |
| Hawaii | $0.37/kWh (high) |
Check your electricity bill for your exact rate — it is usually listed as ¢/kWh or $/kWh under "energy charges."
Energy Cost of Common Appliances
| Appliance | Typical wattage | Hours/day | Monthly cost* |
|---|---|---|---|
| LED bulb (60W replacement) | 9 W | 5 h | $0.18 |
| Laptop | 50 W | 8 h | $1.56 |
| Desktop computer + monitor | 200 W | 8 h | $6.24 |
| Refrigerator | 150 W | 24 h | $14.04 |
| Chest freezer | 100 W | 24 h | $9.36 |
| Window AC (6,000 BTU) | 600 W | 8 h | $18.72 |
| Central AC (3-ton) | 3,500 W | 8 h | $109.20 |
| Electric water heater | 4,000 W | 3 h | $46.80 |
| Clothes dryer | 5,000 W | 1 h | $19.50 |
| EV charging (Level 2) | 7,200 W | 2 h | $56.16 |
*At $0.13/kWh, 30 days/month
Reducing Your Electricity Bill
- Switch to LED bulbs — they use 75–90% less energy than incandescent bulbs
- Unplug vampire loads — devices in standby still draw power (TVs, chargers, game consoles). A smart plug with energy monitoring (such as the Kasa Smart Plug or Emporia Vue) lets you measure exactly what each device is consuming before you run estimates here.
- Upgrade to ENERGY STAR appliances — refrigerators, washers, and ACs with ENERGY STAR ratings use 10–50% less energy
- Use a programmable thermostat — setback 7–10°F for 8 hours/day can save ~10% on heating and cooling
- Run large appliances off-peak — many utilities charge less for nighttime electricity use (time-of-use rates)
Frequently Asked Questions
How do I find my electricity rate? Look at your monthly electricity bill. Divide the total charges (excluding fixed fees) by the total kilowatt-hours used. The result is your effective rate per kWh. Rates are typically between $0.08 and $0.35/kWh in the US.
What uses the most electricity in a home? Heating and cooling (HVAC) typically accounts for 40–50% of a home's electricity use. Water heating is second at 14–18%, followed by appliances (13%), lighting (9%), and electronics (4%). Home EV charging is becoming an increasingly significant load — a nightly full charge on a 75 kWh battery uses roughly the same energy as running central AC for an entire day. If you drive electric, the EV Savings Calculator can help you model how that charging cost compares to what you'd spend fueling a gas vehicle.
How much does it cost to run a TV all day? A modern 55-inch LED TV uses about 80–100 W. Running it 8 hours per day at $0.13/kWh costs about $0.083–$0.104/day, or roughly $2.49–$3.12/month.
