Electricity Cost Calculator
Is that always-on appliance quietly running up your bill? Enter its wattage, how many hours a day you use it, and your electricity rate to see the energy in kWh and what it costs per month and per year.
Your numbers
Result
- Energy per monthkWh
- 150
- Cost per year
- $306.00
| Period | Energy (kWh) | Cost |
|---|---|---|
| Per day | 5 | $0.85 |
| Per month | 150 | $25.50 |
| Per year | 1,800 | $306.00 |
How to calculate running cost
The math is power (kW) × hours per day × days per month. A 1,000 W (1 kW) appliance run 5 hours a day for 30 days uses 1 × 5 × 30 = 150 kWh. At $0.17/kWh that is about $25.50 a month. Add up several appliances to explain your whole bill.
The big energy users
The largest costs are usually things that heat or cool: HVAC and space heaters, water heaters, clothes dryers, refrigerators and ovens. A 1,500 W space heater running much of the day can cost more than everything else combined. Swapping to efficient models (ENERGY STAR, heat-pump, inverter) cuts these the most.
Where to find the wattage and rate
Wattage is on the appliance label or nameplate; if it lists amps, multiply by the voltage (120 or 240 V) to get watts. Your rate ($/kWh) is on your electric bill — watch for tiered rates and time-of-use pricing, where the same appliance costs more at peak hours.
Frequently asked questions
Sources
- Appliance energy use (kWh = kW x hours) and $/kWh rate
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