Which Cooling Tool to Open
When it comes to air conditioning, bigger isn't always better. The process of determining the correct AC capacity, measured in BTUs or tons, is called a cooling load calculation.
HVAC professionals use complex manuals (like ACCA Manual J) to perform these calculations, but our tools provide a highly accurate estimate by accounting for essential variables like your local climate zone, home square footage, ceiling height, and insulation quality. When you know the size, the HVAC installation cost calculators show what it costs installed.
Match the Tool to the Job
- One room, in BTU and tons: start with Tonnage Calculator AC, which also explains what happens when a unit is too big or too small for the room.
- A whole house by square footage: the AC tonnage per square foot chart.
- A central or split system: the central AC size calculator.
- Heating and cooling for the whole house together: the HVAC size calculator, which works from the load and not from square footage alone.
- A system that runs but does not cool: AC not blowing cold air, symptom by symptom.
- Water on the floor or the ceiling: AC leaking water, with the cause found by where the water is.
Jump Straight to an Answer
- AC unit size chart by square footage
- How many square feet each AC ton covers
- Common central split system sizes
- Window air conditioner dimensions and window fit
- Window AC BTU chart beside the ENERGY STAR figures
- Portable AC against window AC, compared
- What each portable AC SACC rating means
Select the calculator above that best matches your needs to get a reliable estimate before you purchase new equipment or request quotes from contractors.