Milli-electron volts to megajoules conversion calculator shown above calculates how many megajoules are in 'X' milli-electron volts (where 'X' is the number of milli-electron volts to convert to megajoules). In order to convert a value from milli-electron volts to megajoules (from meV to MJ) just type the number of meV to be converted to MJ and then click on the 'convert' button.