AC Tonnage Calculator

Estimate air conditioner capacity for a room using a quick sizing tool.

Use the interactive ac tonnage calculator below to get a quick estimate. Results are indicative and should be checked against current market information or qualified advice where appropriate.

How to use this AC tonnage estimate

Start with accurate room dimensions and consider the climate, ceiling height, insulation, occupants and sun exposure. AC tonnage refers to cooling capacity—not the unit’s electricity use. The calculator offers a starting point for comparing 1-ton, 1.5-ton and other models.

What affects AC capacity?

• Room area, ceiling height and insulation
• Afternoon sunlight and window size
• Number of people and heat-producing devices
• Local summer temperatures and humidity

For unusual rooms or large installations, ask an HVAC professional for a heat-load calculation. Read our AC tonnage guide.