Calculate your cost
Start with the example below, then replace the wattage, daily runtime, and rate with the numbers for your window air conditioner.
This setup uses about 240 kWh in a 30-day month.
Please enter valid values within the ranges shown.
| Schedule | Hours/day | Cost/month |
|---|---|---|
| Half runtime | 4 | $22.60 |
| Page example | 8 | $45.19 |
| Longer runtime | 12 | $67.79 |
Same 1,000-watt input and 18.83¢/kWh rate; only runtime changes.
Formula for the page example
1 kW × 8 hr × $0.1883 = $1.51 per day
Convert watts to kilowatts, multiply by the active hours used each day, then multiply by the electricity price in dollars per kWh. Multiply the daily result by 30 for the monthly estimate shown above.
How to read this estimate
A window air conditioner cools one room instead of the whole house, so its total draw is usually lower than a central system's. On a hot day, though, a unit that runs almost continuously can still add a noticeable amount to the bill.
Use this as a baseline until you can check the label or measure the window air conditioner directly. Model, settings, condition, climate, and household routine can all change the result.
What changes the cost?
- 01
Unit size, efficiency, and selected fan speed
- 02
Room area, solar heat gain, and air leakage
- 03
How often the compressor cycles rather than fan-only operation
Ways to spend less
- Choose a unit sized for the room instead of a larger model.
- Close the room and seal gaps around the installation panel.
- Use sleep or eco mode to reduce compressor runtime overnight.