At least one brand of orange soda contains caffeine. One standard 12-ounce serving of Sunkist Orange Soda contains 41 milligrams of caffeine, which is 6 milligrams more than Coca Cola and 3 milligrams more than a standard 12-ounce serving of Pepsi.
Fanta soda, according to the Center for Science in Public Interest, does not contain caffeine, nor do most other brands of orange soda. Barq's Root Beer contains caffeine, though at 23 milligrams, it has 12 milligrams less than a can of Coke. The diet version of Barq's is caffeine free. Most sodas contain from 35 to 69 milligrams of caffeine. The FDA official limit for soft drinks is 71 milligrams.