Cooling cost guide
How much does a portable air conditioner cost to run?
A portable AC can be inexpensive for a few hot hours and costly when it runs all day. Change the sample to match the wattage on your unit and the rate on your bill.
Appliance energy cost
Use the power label on your appliance and the electricity rate shown on your bill.
Formula: watts ÷ 1,000 × hours per day × days × electricity rate. Cycling appliances and variable-speed equipment can use less than their full rated power.
What changes the answer?
Start with input watts, not cooling BTUs
BTU describes cooling capacity. Electricity cost comes from the input power in watts. Use the rated input shown on the product label or manual, then replace it with measured average watts when you have a plug-in meter.
Single-hose and inverter units behave differently
A conventional unit may cycle between full power and off. An inverter model can vary compressor speed. The calculator is most useful when the watts field reflects average draw over a representative hot day.
Room conditions change runtime
Sun exposure, insulation, air leakage, set temperature and outdoor humidity affect how long the compressor runs. Compare scenarios by changing daily hours rather than treating one estimate as a guarantee.
Use this result as a planning range
Do not use an extension cord unless the manufacturer explicitly permits it and the cord is rated for the appliance load.
Review the formulas and public sources in our methodology.