There is an option in the calculator to choose either in game or use the config file for setting your sensitivity and fov, if you set your fov in game it uses vdeg and if you use the config file it uses multiplier - as DPI Wizard said
I attached a screenshot to show you the tab to choose in game or config file in the calculator.
Also the calculator tells you which fov type the game is using, you don't need to set it yourself.