Free tools
Air conditioning calculators for UK homes
Two quick calculators that answer the two questions every buyer asks: what size do I need, and what will it cost to run? Both use the same methods and figures as our guides.
Sizing
BTU calculator: what size air conditioner do I need?
Enter your room size and type, fine-tune for sun, insulation and occupants, and get a recommended capacity in kW and BTU, rounded to the standard unit sizes you will actually find in shops. Built on the same conservative UK sizing method as our buying guides.
Running costs
What does air conditioning cost to run?
Enter your unit's power draw or capacity, how long you run it, and your electricity rate, and get the cost per hour, day, week and season, with the working shown. Defaults to the current Ofgem price cap rate, and you can enter your own tariff.