Diet Coke vs Mountain Dew Zero Sugar: which has more caffeine?

Mountain Dew Zero Sugar has more caffeine than Diet Coke: 68mg vs 46mg in the same 12 oz can. That is a 22mg gap, and since the cans match, the per-serving number is the whole story.

Diet Coke vs Mountain Dew Zero Sugar: the numbers

Sources: Diet Coke's figure is verified in our Diet Coke caffeine guide against Caffeine Informer (source); Mountain Dew Zero Sugar's figure is verified in our Mountain Dew Zero Sugar guide against PepsiCo product facts (source).

Which one should you pick?

Pick Diet Coke when you want the lighter dose or a slower ramp, and Mountain Dew Zero Sugar when you actually need the bigger hit and know your tolerance. If you are stacking either with other caffeinated drinks through the day, run the math against the 400mg reference rather than guessing.

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.

Related reading

• Diet Coke: the full caffeine guide
• Mountain Dew Zero Sugar: the full caffeine guide
• The verified caffeine database
• Every drink compared: the comparisons index

FAQ

Does Diet Coke or Mountain Dew Zero Sugar have more caffeine? Mountain Dew Zero Sugar: 68mg per 12 oz can versus 46mg per 12 oz can for Diet Coke.

Which is stronger per ounce? Mountain Dew Zero Sugar, at about 5.7mg per fluid ounce versus 3.8mg for Diet Coke.