Gallons (US liquid) to barrels (oil) converter on this page calculates how many barrels (oil) are in 'X' gallons (US liquid) (where 'X' is the number of gallons (US liquid) to convert to barrels (oil)). In order to convert a value from gallons (US liquid) to barrels (oil) (from gal to bbl) just type the number of gal to be converted to bbl and then click on the 'convert' button.