BTU Calculator

Estimate the required Air Conditioner (AC) or heater BTU capacity based on room dimensions, ceiling height, and sun exposure.

How to use this calculator

1. Enter room dimensions.
2. Select sun exposure.
3. Read BTU/hr and tons.

Formula & method

HVAC Sizing Model

BTU = Area × 20 × Adjustments

Room load estimation.

Example

180 sq ft room = ~3600 BTU base.

Key insights

• 1 Ton AC = 12,000 BTU/hr.

How to interpret your result

BTU/hr

Heating/cooling load.

Frequently asked questions

Why not oversized?

Oversized AC doesn't dehumidify.

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