How to convert BTU per hour to tons of refrigeration
One BTU per hour equals 0.000083 tons of refrigeration, so multiply the number of BTU per hour by 0.000083:
TR = BTU/h × 0.000083
BTU/h = TR ÷ 0.000083 (1 TR = 12,000 BTU/h)
Example: 9,000 BTU/h → 9,000 × 0.000083 = 0.75 TR.
Going the other way, divide by 0.000083, or multiply by 12,000; the tons of refrigeration to BTU per hour converter does it for you.
Everyday values
| BTU per hour | Tons of refrigeration | For example |
|---|---|---|
| 9,000 BTU/h | 0.75 TR | a 0.75-ton AC |
| 12,000 BTU/h | 1 TR | one ton |
| 18,000 BTU/h | 1.5 TR | 1.5 tons |
| 24,000 BTU/h | 2 TR | 2 tons |
| 36,000 BTU/h | 3 TR | 3 tons |
When you need this conversion
Divide BTU per hour by 12,000 to get tons of refrigeration. Central air systems in the US are sized in tons, mini-splits often in BTU.
BTU per hour to ton of refrigeration conversion table
| BTU/h | TR | BTU/h | TR |
|---|---|---|---|
| 3,000 BTU/h | 0.25 TR | 33,000 BTU/h | 2.75 TR |
| 6,000 BTU/h | 0.5 TR | 36,000 BTU/h | 3 TR |
| 9,000 BTU/h | 0.75 TR | 39,000 BTU/h | 3.25 TR |
| 12,000 BTU/h | 1 TR | 42,000 BTU/h | 3.5 TR |
| 15,000 BTU/h | 1.25 TR | 45,000 BTU/h | 3.75 TR |
| 18,000 BTU/h | 1.5 TR | 48,000 BTU/h | 4 TR |
| 21,000 BTU/h | 1.75 TR | 51,000 BTU/h | 4.25 TR |
| 24,000 BTU/h | 2 TR | 54,000 BTU/h | 4.5 TR |
| 27,000 BTU/h | 2.25 TR | 57,000 BTU/h | 4.75 TR |
| 30,000 BTU/h | 2.5 TR | 60,000 BTU/h | 5 TR |
About the units
- BTU per hour (BTU/h): one International Table BTU per hour, about 0.2931 W.
- Ton of refrigeration (TR): 12,000 BTU per hour, about 3.517 kW.
Both are units of power. The conversion factor comes from the exact definitions above, so the calculator is exact; results are only rounded for display (up to six significant digits).
Frequently asked questions
How many tons of refrigeration are in one BTU per hour?
One BTU per hour is 0.000083 tons of refrigeration. One ton of refrigeration is 12,000 BTU per hour.
How do I convert BTU per hour to tons of refrigeration?
Multiply the value in BTU per hour by 0.000083. To go back, divide by 0.000083.
What is 9,000 BTU/h in tons of refrigeration?
9,000 BTU/h = 0.75 TR.
What is 12,000 BTU/h in tons of refrigeration?
12,000 BTU/h = 1 TR.
Sources
- NIST Special Publication 811 (2008), Guide for the Use of the International System of Units (SI), Appendix B: conversion factors.
- NIST Handbook 44 (2024), Appendix C: General tables of units of measurement.
Last reviewed 5 October 2026. Results are estimates; see our disclaimer.