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