What Size Air Con Do I Need?
Enter your room's size and a few details and we'll work out the cooling capacity in BTU you need, then show which portable units and split systems cover it.
Describe the room
You need about
9,000 BTU
≈ 2.6 kW cooling
Recommendation
Large portable
You need a larger 9,000–12,000 BTU portable, or consider a fixed split.
- Meaco MeacoCool MC9000CHCheck price9,000 BTU · enough for this room
- Pro Breeze Pro Breeze 9,000 BTU 3-in-1 SmartCheck price9,000 BTU · enough for this room
- Black+Decker Black+Decker BXAC40025GBCheck price9,000 BTU · enough for this room
- AEG ChillFlex Pro AXP26Check price9,000 BTU · enough for this room
- Igenix Igenix IG9919Check price9,000 BTU · enough for this room
- Meaco MeacoCool MC10000CHCheck price10,000 BTU · enough for this room
- De'Longhi Pinguino PAC EX100 SilentCheck price10,000 BTU · enough for this room
- De'Longhi Pinguino PAC EL98 ECO SilentCheck price10,700 BTU · enough for this room
- Russell Hobbs Russell Hobbs RHPAC11001Check price11,000 BTU · enough for this room
- Pro Breeze Pro Breeze 12,000 BTU 4-in-1 SmartCheck price12,000 BTU · enough for this room
- Russell Hobbs Russell Hobbs RHPAC12001Check price12,000 BTU · enough for this room
- Black+Decker Black+Decker BXAC40008GBCheck price12,000 BTU · enough for this room
- Meaco MeacoCool MC7000CH7,000 BTU · too small for this room
- EcoFlow EcoFlow Wave 36,100 BTU · too small for this room
Indicative sizing based on floor area, ceiling height, sun, occupancy and heat load. Rounds up to the nearest 500 BTU. A quick survey confirms the exact size for your room.
Assumptions
- Electricity price
- 26.32p/kWh, Ofgem price cap, 1 October to 31 December 2026 (Ofgem)
- Duty cycle
- 75% of the time running on a typical day (thermostat cycling); 100% in a heatwave
- Sizing
- 430 BTU/m² at 2.4m ceiling, adjusted for insulation, sun, occupants and electronics, rounded up to 500 BTU
Rates checked 20 September 2026. Check them again before you commit to anything.
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