BTU (IT) per second to cubic feet de natural gas per second converter on this page calculates how many cubic feet de natural gas per second are in 'X' BTU (IT) per second (where 'X' is the number of BTU (IT) per second to convert to cubic feet de natural gas per second). In order to convert a value from BTU (IT) per second to cubic feet de natural gas per second type the number of BTU/s to be converted to cubic feet de natural gas per second and then click on the 'convert' button.