Diet Coke
Diet Coke does not use a modified form of the Coca-Cola recipe, but instead an entirely different formula. The controversial New Coke, introduced in 1985, used a version of the Diet Coke recipe that contained high fructose corn syrup and had a slightly different balance of ingredients. In 2004, Coca-Cola introduced Coca-Cola C2, which it claims tastes much closer to Coca-Cola but contains half the carbohydrates. In 2005, the company introduced Coca-Cola Zero (replaced by "Coca-Cola Zero Sugar" in 2017), a sugar-free variation of regular Coca-Cola.
Pepsi Zero Sugar
Pepsi Zero Sugar competes in the energy drink market, as is implied by it being marketed as an 'Invigorating Cola.' Compared with other common energy drinks, Pepsi Zero Sugar gives the consumer a relatively low dose of caffeine. Pepsi Zero Sugar provides 5.75 mg caffeine per 30ml, while Red Bull provides 9.64 mg/30ml, AMP Energy provides 8.93 mg/30ml, Monster Energy provides 10 mg/30ml and Cocaine provides 33.14 mg/30ml. Pepsi Zero Sugar commercials present the beverage as an alternative to Diet Pepsi.