Pounds per square foot to millipascals conversion calculator shown above calculates how many millipascals are in 'X' pounds per square foot (where 'X' is the number of pounds per square foot to convert to millipascals). In order to convert a value from pounds per square foot to millipascals (from psf to mPa) simply type the number of psf to be converted to mPa and then click on the 'convert' button.