Acre-feet to gallons (US liquid) conversion calculator shown above calculates how many gallons (US liquid) are in 'X' acre-feet (where 'X' is the number of acre-feet to convert to gallons (US liquid)). In order to convert a value from acre-feet to gallons (US liquid) (from ac ft to gal) simply type the number of ac ft to be converted to gal and then click on the 'convert' button.