Diet Pepsi Caffeine Content

Here you will learn about the caffeine in Diet Pepsi. Specifically, we discuss the amount in its popular sizes. Additionally, we provide a comparison of Diet Pepsi to other drinks with caffeine. By the end of this article, you should have a solid understanding of the caffeine in this soda. Let’s get into it!

How Much Caffeine In Diet Pepsi?

Diet Pepsi contains approximately 2.93 milligrams (mg) of caffeine per ounce. Here is the amount of caffeine found in its single-serve cans/bottles:

Serving SizeCaffeine(mg)
7.5 fl. oz.22mg
8 fl. oz.24mg
8.45 fl. oz.25mg
10 fl. oz.30mg
12 fl. oz.35mg
16 fl. oz.47mg
16.9 fl. oz.50mg
20 fl. oz.59mg

Diet Pepsi Ingredients

Diet Pepsi contains added caffeine. It does not come from a natural source like tea. Since caffeine is an added ingredient, it appears in the list of ingredients that you see on the label.

Ingredients: Carbonated Water, Caramel Color, Aspartame, Phosphoric Acid, Potassium Benzoate, Caffeine, Citric Acid, Natural Flavor, Acesulfame Potassium.

Cola manufacturers state that they add caffeine to cola to produce its unique taste. It reportedly provides a bitter flavor that helps balance the sweetness. Furthermore, caffeine certainly helps sales as about 85% of U.S. adults consume the stimulant daily.

Caffeine Comparison

The caffeine in Diet Pepsi is relatively similar to what is found in Pepsi, Coca-Cola, and Coke Zero, as examples. Its caffeine level is typically for a soda and much less than countless coffee and energy drinks.

Keep in mind that health agencies typically advise adults to consume no more than 400 mg of caffeine daily. That is almost 11.5 cans or roughly 138 ounces of Diet Pepsi. We think that it’s safe to say that most people don’t come close to drinking 400 mg of caffeine simply from Diet Pepsi.

BeverageServing SizeCaffeine (mg)
Diet Pepsi12 fl. oz.35
Coke Zero12 fl oz34
Diet Coke12 fl oz46
Pepsi Zero Sugar12 fl oz69
Diet Dr Pepper12 fl oz41
Coca-Cola Classic12 fl 34
MTN Dew12 fl oz54
Diet MTN Dew12 fl oz54
Pepsi12 fl oz38
RC Cola12 fl oz43
Red Bull12 fl oz114
Monster Energy12 fl oz120
Coffee12 fl oz136*
*Source – USDA. Caffeine is approximate.

Mitchell, D. C., Knight, C. A., Hockenberry, J., Teplansky, R., & Hartman, T. J. (2013, November 1). Beverage caffeine intakes in the U.S. Food and Chemical Toxicology. Retrieved November 16, 2022, from
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