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Free Tool - Calculator

BTU Calculator

Estimate the cooling capacity a room actually needs, so you can sanity-check any system size you are quoted.

Your details

Everything updates as you change it. Nothing is sent anywhere.

Desert heat load runs about 25% above the national sizing rule of thumb.

Recommended cooling capacity

6,000 BTU

Room area
224 ft²
Roughly equivalent to
0.5 tons

Single-zone mini split

A 9,000 BTU (0.75 ton) ductless head covers this comfortably. Common for a converted garage, casita or home office.

Want this checked against your whole house?

Room-by-room math is a good sanity check. Sizing a system you are about to buy needs a load calculation on the entire home, and we will run one without sending a salesperson.

Optional message describing your situation or what we should know before contacting you.

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California privacy notice (CCPA/CPRA). Categories of PI collected: identifiers (name, email, phone), commercial info (service requested), internet activity (referring page). We do not sell or share for cross-context behavioral advertising. CA residents have rights to know, delete, correct, and limit use of sensitive PI. See the Privacy Policy or call (818) 690-7951.

No sales visit booked without your say-so. We do not sell your details.

This is a room-level estimate using standard sizing rules plus a regional climate adjustment. It is not a Manual J load calculation and should not be used on its own to buy equipment. Real sizing depends on insulation, window glazing, duct condition, infiltration and orientation.
Related services

What this usually leads to

AC Installation & Replacement Ductless Mini Splits AC Repair
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Ready for an Honest Number?

Run a real load calculation online, or call the team in your state. Flat-rate pricing either way, and nobody shows up to sell you something bigger than you need.

Get Your TrueQuote (480) 435-2334
Flat-rate pricing, no upsells Parts and labor warranty Licensed in AZ and CA

California team: (818) 690-7951 · Text us: (818) 489-2826