Pounds-force to millinewtons conversion calculator above calculates how many millinewtons are in 'X' pounds-force (where 'X' is the number of pounds-force to convert to millinewtons). In order to convert a value from pounds-force to millinewtons (from lbf to mN) simply type the number of lbf to be converted to mN and then click on the 'convert' button.