Kilo-electron volts to gigajoules conversion calculator shown above calculates how many gigajoules are in 'X' kilo-electron volts (where 'X' is the number of kilo-electron volts to convert to gigajoules). In order to convert a value from kilo-electron volts to gigajoules (from keV to GJ) type the number of keV to be converted to GJ and then click on the 'convert' button.