How much caffeine is in Diet Dr Pepper?

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Diet Dr Pepper has 41mg of caffeine per 12 oz can, per Caffeine Informer. That works out to about 3.4mg per fluid ounce, well under brewed coffee at 11.9mg per ounce. Against the two standards everyone actually knows, one 12 oz can equals about 0.4 cups of brewed coffee or 0.7 shots of espresso.

Diet Dr Pepper vs coffee and espresso

How the number behaves

Sodas list an exact caffeine number because caffeine is a measured additive: every 12 oz can of Diet Dr Pepper carries the same 41mg, unlike brewed coffee, where the beans, dose, and brew time move the figure around. That predictability is the one real advantage a can has over a cup: you always know exactly what you drank.

The mistake people make is treating it as caffeine-free because it is "just a soda." At 41mg per 12 oz can, it takes about 10 servings to reach the 400mg FDA reference, but every serving still counts toward the same daily total as your coffee does.

Where to find it

Check Diet Dr Pepper prices on Amazon

Compare it

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For context, the FDA cites 400mg of caffeine a day as an amount generally not associated with negative effects in healthy adults. Tolerance and health vary, so treat these numbers as information, not advice.

FAQ

How much caffeine is in Diet Dr Pepper? 41mg per 12 oz can, per Caffeine Informer. That is about 3.4mg per fluid ounce.

Is Diet Dr Pepper stronger than coffee? No. Diet Dr Pepper carries 41mg per 12 oz can versus 95mg in an 8 oz cup of brewed coffee, and per ounce it is 3.4mg versus 11.9mg.

How many servings of Diet Dr Pepper reach 400mg of caffeine? About 9.8 of the 12 oz can servings reach the 400mg daily amount the FDA cites for healthy adults.

Sources: the Diet Dr Pepper figure (41mg per 12 oz can) is Caffeine Informer (source). Brewed coffee (95mg per 8 oz) and espresso (63mg per 1 oz) reference values are from USDA FoodData Central (source).