Calories per second to BTU (IT) per hour converter above calculates how many BTU (IT) per hour are in 'X' calories per second (where 'X' is the number of calories per second to convert to BTU (IT) per hour). In order to convert a value from calories per second to BTU (IT) per hour (from cal/s to BTU/h) just type the number of cal/s to be converted to BTU/h and then click on the 'convert' button.