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Mini Split Size Calculator

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Mini Split Size Calculator

Estimate an approximate BTU range for one room or small space. The result is a starting point, not final equipment sizing.

Room details

Use feet.
Use feet.
Most standard rooms are near 8 ft.
Use the typical number of people in the room.

Calculator result

The calculator starts with room square footage, then adjusts for ceiling height, insulation, sun exposure, occupants, and kitchen heat.

How to use the result

Use the BTU range as a first-pass planning number. If your room is open to other spaces, has large windows, has unusual construction, or is difficult to heat or cool, the result may be less reliable.

A qualified HVAC professional can perform a Manual J load calculation and account for details this simple calculator does not include.

Related next steps

BTU calculatorRun a simpler BTU-only estimate.AC tonnage converterConvert BTU sizing to tons.Room square footage calculatorMeasure room area first.Mini split sizing chartCompare common size ranges.What size mini split do I need?Understand the sizing factors.Oversized vs undersizedLearn why cautious sizing matters.Bedroom mini splitSizing notes for bedrooms.Garage mini splitSizing notes for garages.What is BTU?Learn the main sizing unit.What is AC tonnage?Understand tons of cooling.DisclaimerReview calculator limitations.Editorial policyHow content is created and reviewed.