AC Unit Tonnage / Sizing Calculator
AC Size by Square Footage
Estimate AC tonnage based on home size and conditions
Room / Window AC Size
Size a window or portable AC unit for a single room
Formula
BTU = Sq Ft x 20 x Climate Factor x Insulation Factor x Sun Factor | Tons = BTU / 12,000
Frequently Asked Questions
How many tons of AC do I need per square foot?
The general rule is 1 ton of cooling per 500-600 square feet of living space. A 2,000 sq ft home typically needs a 3.5-4 ton unit. However, climate, insulation, sun exposure, and ceiling height all affect the actual requirement.
What happens if my AC unit is too big?
An oversized AC will short-cycle (turn on and off frequently), leading to poor humidity control, uneven temperatures, higher energy bills, and increased wear on the compressor. Proper sizing is essential for comfort and efficiency.
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