Giga-electron volts to nanojoules conversion calculator above calculates how many nanojoules are in 'X' giga-electron volts (where 'X' is the number of giga-electron volts to convert to nanojoules). In order to convert a value from giga-electron volts to nanojoules (from GeV to nJ) type the number of GeV to be converted to nJ and then click on the 'convert' button.