Same caffeine as regular Pepsi
Pepsi Zero Sugar is a sugar-free cola with the same caffeine content as regular Pepsi. PepsiCo Product Facts list 38 mg of caffeine in a 12 oz serving. A standard 20 oz bottle therefore contains about 63 mg, and a 2-liter bottle contains roughly 211 mg total.
The zero-sugar formulation removes the calories but not the caffeine. If you are switching from regular Pepsi to Pepsi Zero Sugar for health reasons, your caffeine intake does not change.
Soda caffeine adds up across the day
Colas are a common hidden source of caffeine because people do not always think of them as caffeinated drinks. Two 20 oz bottles of Pepsi Zero Sugar deliver about 126 mg, which is more than a small coffee. For someone staying under the FDA’s 400 mg daily reference for healthy adults, that is nearly a third of the daily allowance from soda alone.
The caffeine level is also similar to Coca-Cola Classic and Diet Coke, so brand switching does not meaningfully change the dose.
Why zero sugar does not mean zero caffeine
Sugar-free soft drinks replace sugar with sweeteners but keep the same caffeine dose as their regular counterparts. The caffeine contributes to the familiar cola taste and the mild stimulating effect. If you drink multiple cans throughout the day, the caffeine can accumulate to a meaningful total even though each individual serving looks small.
Source
The 38 mg per 12 oz figure is from PepsiCo Product Facts for Pepsi Zero Sugar, checked 19 September 2026.