AC size calculator · Phoenix & West Valley

What Size AC Do I Need?

Answer four quick questions about your home and see an estimated AC size in tons, based on Phoenix-area rules of thumb.

Tell us about your home

Four quick questions. Your answers stay on this page.

Cooled square footageYour listing, appraisal or county assessor record usually has it.Stories

How much sun does the house get?

Mostly shadedTrees or neighboring homes shade it most of the dayAverageTypical sun exposureLots of sunBig west- or south-facing windows, little shade

Insulation and windows

Newer or updatedBuilt after about 2000, or insulation and windows upgradedOlderOriginal insulation and single-pane windows

Ceiling height

About 8 ft9–10 ftVaulted or 12 ft+

AC sizing questions

What size AC do I need for my house in Arizona?

In the Phoenix area, a common rule of thumb is about 1 ton of cooling for every 450–500 square feet, adjusted for sun exposure, insulation, windows and ceiling height. A 1,800 sq ft home with average sun usually lands around 3.5 to 4 tons. A load calculation gives the exact size.

What size AC do I need for 2,000 square feet?

Most 2,000 sq ft homes in the Phoenix area need roughly 4 to 4.5 tons, depending on sun, insulation and ceilings. Homes with lots of west-facing glass or older insulation may need more.

Is a bigger AC better?

No. An oversized AC cools in short bursts, which wastes energy, wears out parts faster and leaves the house feeling clammy. An undersized AC runs nonstop on the hottest days. The right size matters more than the biggest size.

What is a load calculation?

A load calculation measures how much heat your home gains, based on square footage, windows, insulation, orientation and ductwork. It’s the professional way to size a system, and we do one free with every new system estimate.

Know your size? See an instant price range with our New AC Price Estimator.