AC Tonnage Calculator
Convert between BTU/hr and AC tons at 12,000 BTU per ton, or estimate tonnage from floor area.
Processed locally in your browser — nothing is uploaded.
AC Tonnage Calculator
Results
- Tonnage
- 2 tons
- BTU/hr
- 24,000
- Nearest common unit size
- 2 tons
12,000 BTU/hr per ton of cooling
Residential units come in half-ton steps (1.5, 2, 2.5, …)
Area-based sizing is a rough guide; insulation, climate, and windows change the real load.
About AC Tonnage Calculator
One "ton" of air conditioning moves 12,000 BTU per hour. This converter goes both directions and includes an area mode that estimates tonnage from floor area at 20 BTU per square foot, then suggests the nearest half-ton unit size.
Common uses
- Decode a model number's BTU rating into tons
- Ballpark the tonnage for a 1,600 sq ft house before getting quotes
Example
Input
24,000 BTU/hr
Output
2.0 tons
Limitations
- Area-based estimates ignore climate, insulation, and windows — use the BTU calculator or a Manual J for sizing
Frequently asked questions
How many BTU is a 3-ton air conditioner?
36,000 BTU per hour. One ton is defined as 12,000 BTU/hr, so 2 tons is 24,000, 2.5 tons is 30,000, and 4 tons is 48,000.
Why is air conditioning measured in tons?
It dates back to ice: a "ton" of cooling is the rate at which melting one ton of ice absorbs heat over 24 hours — 288,000 BTU spread across a day, or 12,000 BTU per hour. It says nothing about how much the equipment weighs.
What size AC do I need for a 1,600 square foot house?
About 2.7 tons at the 20 BTU per square foot rule of thumb (32,000 BTU/hr), which this tool rounds to the nearest half-ton unit size of 2.5 tons. Treat that as a starting point for quotes, not a specification.
Can I size an air conditioner from square footage alone?
Not reliably. Floor area ignores climate, insulation, window area and orientation, ceiling height, and duct losses, all of which move the real load substantially. Use the BTU calculator for a rough adjustment, and a contractor's Manual J load calculation before buying a system.
Is anything I type here sent to a server?
No. The BTU-to-tons conversion runs in your browser as you type — the capacities and floor areas you enter are never transmitted or stored.