How to use the refrigeration capacity converter
Refrigeration capacity is quoted in tons, BTU/h, kW or kcal/h depending on the catalog. Enter one value, pick the unit it was written in (US tons are the default), and the page returns the other four units at once, US tons and BTU/h first, and states which refrigeration-ton basis it read the input as. It is meant for lining up quotations and spec sheets that use different units.
Conversion runs through watts as the pivot. The US ton is 1 ton = 12,000 BTU/h = 3.516853 kW (about 3,024 kcal/h), the Korean and Japanese ton is 1 RT = 3,320 kcal/h, and the heat-rate links are 1 BTU/h = 0.29307107 W and 1 kcal/h = 1.163 W. For example 10 tons is 120,000 BTU/h or 35.1685 kW. The ratio between the two tons, 3,320 to 3,024, is about 9.8%, so mixing the bases shifts a selection by a whole step. These relations are derived from the definitions, the sources are secondary and current as of October 2026, and the original standards are worth checking.
The Korean and Japanese RT is kept only for reading imported catalogs; for US equipment the ton and BTU/h lines are the ones to use. Equipment selection and load calculation are not covered here. This is a reference aid and does not replace design work; review by a qualified engineer is required.
Frequently asked questions
The reference values differ. Korea and Japan treat 1 RT as 3,320 kcal/h, while the US ton is 12,000 BTU/h, or about 3,024 kcal/h. The same nominal ton therefore differs by about 10%.
It cannot be settled from the letters alone. Check the kcal/h or BTU/h figure next to it: a 3,320 family number means the Korean and Japanese basis, and 12,000 BTU/h means the US basis.
The page uses 1 BTU/h = 0.29307107 W and 1 kcal/h = 1.163 W, so 1 US ton lands on exactly 12,000 BTU/h, or 3.516853 kW.