Gigabars to inches of water conversion calculator shown above calculates how many inches of water are in 'X' gigabars (where 'X' is the number of gigabars to convert to inches of water). In order to convert a value from gigabars to inches of water (from Gbar to inH2O) type the number of Gbar to be converted to inH2O and then click on the 'convert' button.