Pepsi has more caffeine than Coca-Cola Zero Sugar: 38mg vs 34mg in the same 12 oz can. That is a 4mg gap, and since the cans match, the per-serving number is the whole story.
Coca-Cola Zero Sugar vs Pepsi: the numbers
| Coca-Cola Zero Sugar | Pepsi | |
|---|---|---|
| Caffeine per serving | 34mg per 12 oz can | 38mg per 12 oz can |
| Caffeine per fl oz | 2.8mg | 3.2mg |
| Servings to reach 400mg (FDA context) | 11.8 | 10.5 |
Sources: Coca-Cola Zero Sugar's figure is verified in our Coca-Cola Zero Sugar caffeine guide against Caffeine Informer (source); Pepsi's figure is verified in our Pepsi guide against Caffeine Informer (source).
Which one should you pick?
Pick Coca-Cola Zero Sugar when you want the lighter dose or a slower ramp, and Pepsi 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
- Coca-Cola Zero Sugar: the full caffeine guide
- Pepsi: the full caffeine guide
- The verified caffeine database
- Every drink compared: the comparisons index
- Compare any two of 120+ drinks
FAQ
Does Coca-Cola Zero Sugar or Pepsi have more caffeine? Pepsi: 38mg per 12 oz can versus 34mg per 12 oz can for Coca-Cola Zero Sugar.
Which is stronger per ounce? Pepsi, at about 3.2mg per fluid ounce versus 2.8mg for Coca-Cola Zero Sugar.
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