Electricity cost calculator
Use the energy information you have: watts and hours, annual kWh from a label, a meter reading, or kWh per completed load. Enter your electricity price or start with a US state average. Power presets are examples; label and meter inputs start blank.
Calculate your electricity cost
Use watts and running time, or enter energy from a label, meter or completed load. Your inputs stay on this device.
Enter a number within each field’s limits to calculate your cost.
Your estimated energy cost
460 kWh across 365 use days per year
Power mode includes your selected duty cycle. The monthly figure assumes 30.44 use days; the annual total uses your selected use days. These are estimates at the entered rate.
Energy charges only. Fixed utility fees, purchase, installation and maintenance are excluded. See the calculation method and sources.
The formula, in the open
Electricity cost = kWh × your price in dollars per kWh. In power mode, kWh per day = watts ÷ 1,000 × hours × duty-cycle percentage ÷ 100. Direct-energy modes use your entered kWh without applying watts, hours or duty again. The calculation method explains the assumptions.
For appliance-specific measurement advice and comparisons using state electricity prices, every appliance preset also has its own page: pick from all 40 appliances or browse rates by state.
Choose the calculation that matches your information
- Annual energy: enter kWh/year from a label or specification. Annual cost is kWh × price, and its monthly average is annual cost ÷ 12.
- Metered energy: enter recorded kWh and elapsed days. The first result prices that measurement; the monthly and annual projections assume the same daily average.
- Energy per use: enter kWh for a completed load or session and your schedule. At an illustrative 20 cents/kWh, 3 kWh/load costs $0.60; four loads/week for 52 weeks uses 624 kWh and costs $124.80, or $10.40 per month averaged over the year.
These direct-energy modes do not apply an additional duty cycle. The FTC explains EnergyGuide labels and why the printed annual dollar cost can differ from your cost.
How do I calculate the running cost of an appliance?
Multiply the power draw in kilowatts by the hours used per day and by your electricity rate per kWh. A 1500W heater at full power for 4 hours a day at an illustrative 20 cents per kWh costs 1.5 x 4 x $0.20 = $1.20 a day. The calculator above does this, and also accounts for duty cycle.
Where do I find the wattage of my appliance?
Check the nameplate sticker or plate, usually near the power cord, the model label, or the manual. Look for electrical input in watts (W), which may be a maximum. Volts times amps gives apparent power and can overstate real watts for motors and electronics. Measured energy or model-specific data is preferable.
What is a duty cycle and when should I change it?
Duty cycle is the share of switched-on time an appliance actually draws power. Thermostat-controlled equipment - fridges, heaters, air conditioners - cycles on and off, so a fridge that is plugged in 24 hours a day might draw power only a third of that time. For a fixed operating wattage on lights, TVs and fans, use 100%. If your input is already average measured watts, also use 100% so off-time is not counted twice.
Which electricity rate should I use?
Use the applicable usage-based price in cents per kWh, including usage-based delivery charges. Fixed fees are separate. Time-of-use and tiered tariffs need a rate for the hours or usage being estimated. A state preset supplies the EIA benchmark for August 2026.