Gallons (UK) to fluid ounces (US) converter on this page calculates how many fluid ounces (US) are in 'X' gallons (UK) (where 'X' is the number of gallons (UK) to convert to fluid ounces (US)). In order to convert a value from gallons (UK) to fluid ounces (US) (from gal to fl oz) simply type the number of gal to be converted to fl oz and then click on the 'convert' button.