As the others have said, Coke Zero contains aspartame. However, it also contains acesulfame potassium which is another sweetener, so it may have a little less a

As the others have said, Coke Zero contains aspartame. However, it also contains acesulfame potassium which is another sweetener, so it may have a little less aspartame than Diet Coke. (The effect of multiple sweeteners is generally greater than an equivalent larger dose of one... or so I have... read. Maybe. In something somewhere. No promises.)