HVAC Load Calculator

Estimate the BTU and ton capacity you need to heat or cool your home using a Manual J–style rule of thumb.

Recommended capacity
50,625 BTU/hr
Approx. 4.2 tons

Rule-of-thumb estimate. A Manual J load calculation by a licensed HVAC contractor is required for correct sizing.

Frequently asked questions

Is this the same as Manual J?

No. Manual J is a detailed room-by-room load calculation by a licensed HVAC contractor. This tool gives a quick estimate.

Can I just use square footage?

Square footage alone often oversizes equipment. Climate, insulation, and ceiling height matter.

What size AC do I need?

1 ton (12,000 BTU) cools about 400–600 sq ft in a moderate climate.

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