About this Appliance Electricity Cost Calculator
Appliances turn watts and hours into kWh on your utility bill. This calculator estimates how much one appliance costs to run over a day, month, and year.
Who this calculator is for
- Homeowners and renters estimating utility bill impact.
- People comparing old and efficient appliances.
- Households checking standby or high-use appliance costs.
When to use it
- Estimate refrigerator, heater, fan, dehumidifier, or dryer cost.
- Compare appliance wattage before buying a replacement.
- Convert daily use into monthly and annual energy cost.
How to use this calculator
- Enter the appliance wattage.
- Enter hours used per day.
- Adjust duty cycle for appliances that cycle on and off.
- Enter electricity price and review daily, monthly, and annual cost.
Key assumptions
- A 30.4375-day average month is used for monthly cost.
- Usage and wattage are assumed steady for the entered duty cycle.
- Calculations run locally and are for planning only.
Dataset sources
EIA retail electricity price data
- Effective date
- 2024
- Last reviewed
- 2026-05-05
State and national average retail rates are planning references, not a utility tariff or time-of-use schedule.
Public U.S. Energy Information Administration data.
Accuracy and testing
Review formula sources, default test cases, assumptions, unit handling, rounding rules, and changelog for this calculator.
How this calculator works
Daily kWh = watts / 1000 x hours per day x duty cycle. Daily cost = daily kWh x electricity price.
Daily kWh = watts / 1000 * hours per day * duty cycle percent / 100. Cost = kWh * electricity rate.
Inputs explained
Wattage
Power draw from the appliance label, smart plug, or spec sheet.
Duty cycle
Percent of the entered hours when the appliance is actively drawing that wattage.
Electricity rate
Your utility price per kWh, including delivery if you want all-in cost.
Understanding your results
The annual cost assumes the same usage every day. Seasonal appliances may need a shorter period or lower daily average.
Example scenarios
Space heater
1,500 W for 4 hours/day at 100% duty cycle and $0.18/kWh costs $1.08 per day.
Key Features
- Instant Calculation
- Private & Secure
- Mobile Optimized
Tips & Best Practices
- Use a plug-in energy meter for variable appliances when possible.
- For refrigerators and HVAC, duty cycle matters more than nameplate wattage.
- Use all-in utility rates if your bill separates supply and delivery charges.