Updated August 24, 2026
Air Conditioner Running Cost Calculator
Free air conditioner running cost calculator. Find hourly, daily, and monthly electricity cost for window, portable, mini-split, or central AC using your own tariff.
Live calculator
Calculate your actual running cost
Running this air conditioner for 8 hours a day, 7 days a week uses about 364.0 kWh each month.
Quick answer
How much does an air conditioner cost to run?
A 1,500 W air conditioner used for 8 hours a day, 7 days a week, consumes about 364.0 kWh per month. At £0.2611 per kWh (Ofgem GB illustration for Jul–Sep 2026), that is approximately £95.04 per month. Replace these example figures with the wattage and electricity rate from your appliance and bill.
What changes the real running cost?
Air-conditioner input power varies with cooling capacity, efficiency, outdoor temperature, and thermostat cycling. Use the electrical input watts, not the cooling-output rating.
If the compressor cycles off regularly, use fewer effective hours than the total time the unit is switched on.
Assumptions used in this example
This page starts with 1,500 watts, 8 hours of use per day, and 7 days per week. Those defaults are only a practical starting point. Replace them with the number on your product label, energy label, smart plug, or electricity bill.
Example air conditioner costs
These examples use 1,500 W for 8 hours a day and 7 days per week.
| Electricity rate | Per hour | Per month | Per year |
|---|---|---|---|
| £0.20 / kWh | £0.30 | £72.80 | £873.60 |
| £0.26 / kWh | £0.39 | £95.04 | £1140.48 |
| £0.35 / kWh | £0.52 | £127.40 | £1528.80 |
Ways to reduce the cost
Start with changes that reduce active runtime without compromising safety or the job the appliance needs to do.
- Set the thermostat a little higher.
- Clean filters and keep vents clear.
- Shade sun-facing windows during the hottest hours.
Estimate only. Actual consumption varies by model, setting, condition, temperature, duty cycle, and tariff. Use a plug-in meter or energy-label figure when accuracy matters.
FAQ
Air conditioner running cost questions
How do I calculate air conditioner running cost?
Divide the watts by 1,000 to get kilowatts, multiply by the hours used, then multiply by your electricity price per kWh. This page pre-fills 1,500 W, 8 hours per day, and 7 days per week as a starting example.
How much does an air conditioner cost per hour?
At 1,500 W and £0.2611 per kWh (an Ofgem GB cap illustration), the example cost is about £0.39 per hour while it is actively using that power. Change the rate field to match your own bill.
Why might my real air conditioner cost be different?
If the compressor cycles off regularly, use fewer effective hours than the total time the unit is switched on.
Should I use rated watts or measured watts?
Rated watts are useful for a quick estimate, but measured wall power or an energy-label kWh figure is usually more accurate because many appliances cycle on and off or change power during use.
Does the calculator include standing charges, taxes, or demand charges?
No. The calculator estimates usage cost from kWh only. If your bill includes standing charges, taxes, delivery fees, or demand charges, add those separately.
Can I share my result?
Yes. Use the share or copy button after entering your wattage, hours, days, rate, and currency. The page stores those inputs in the URL so you can revisit the same estimate.