Acre-feet to barrels (oil) conversion calculator above calculates how many barrels (oil) are in 'X' acre-feet (where 'X' is the number of acre-feet to convert to barrels (oil)). In order to convert a value from acre-feet to barrels (oil) (from ac ft to bbl) just type the number of ac ft to be converted to bbl and then click on the 'convert' button.