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AC / Cooling Size Calculator

Get a preliminary room AC capacity range.

Measurements

Your result

Enter your details and select Calculate.

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How it works

Use the ENERGY STAR room-size guidance for 8 ft ceilings, then adjust broadly for ceiling height and sun.

Simple example

A 250 sq ft average-sun room starts around 6,000 BTU/h.

Common question

Is this an HVAC load calculation?

No. Insulation, climate and occupants affect sizing; professional sizing may be needed.

This is a planning estimate. Check product instructions, dimensions and site conditions before purchasing or building.

Sizing reference: ENERGY STAR room air conditioners.