Watts to BTU (IT) per minute conversion calculator shown above calculates how many BTU (IT) per minute are in 'X' watts (where 'X' is the number of watts to convert to BTU (IT) per minute). In order to convert a value from watts to BTU (IT) per minute (from W to BTU/min) type the number of W to be converted to BTU/min and then click on the 'convert' button.