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What air conditioner size (BTU)?

Before buying an air conditioner, this calculator estimates the cooling capacity you need in BTU from the area, ceiling height, sun exposure, insulation and number of occupants. An undersized unit runs constantly without cooling.

What air conditioner size (BTU)?
Estimate the cooling capacity you need in BTU from the room area, sun exposure, insulation and number of occupants.
Indicative ranges based on market tiers. Prices and availability may vary.
Methodology

This calculator produces an indicative estimate based on the parameters you enter. The ranges used reflect typical market tiers in the space and are neither a commercial offer nor a guarantee. Prices and availability may vary.

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Frequently asked questions

How many BTU for 25 m²?

About 8,500 BTU for 25 m² under 2.5 m with average exposure. Expect 9,000 to 12,000 BTU if the room faces south, is poorly insulated or sits under the roof.

BTU, watts, frigories: what is the difference?

They are three units for the same power: 1 BTU/h ≈ 0.293 W and 1 frigorie/h ≈ 1.16 W. Product pages often show BTU, spec sheets show watts.

Does a more powerful unit cool faster?

No: an oversized unit reaches the setpoint too quickly, stops, then restarts. It dehumidifies poorly and uses more energy. Getting the right size matters more.

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