Although these two products are from the same company, there are still some differences between the two, especially when you compare some of the materials that make up their content. Diet Pepsi is the older of the two who have been around since 1964, whereas Pepsi Max was introduced in 1993 to serve as an alternative to the former. Since there are about three main types of Pepsi Max in the market, their taste actually depends on what makes up each type. For instance, Pepsi Max Punch, which is a type of Pepsi Max, has ginger and cinnamon as part of its ingredients. Pepsi Max Twist contains lime. Pepsi Max Cappuccino contains coffee.
As for Diet Pepsi, its common types or variants are Diet Wild Cherry Pepsi, Diet Pepsi Lemon Twist, and Diet Pepsi Lime Twist. Another difference between the two is that Pepsi Max has a higher calorie compared to Diet Pepsi. Also, Pepsi Max has higher caffeine content compared to Diet Pepsi.