Mello Yello has more caffeine than Pepsi: 51mg vs 38mg in the same 12 oz can. That is a 13mg gap, and since the cans match, the per-serving number is the whole story.
Pepsi vs Mello Yello: the numbers
| Pepsi | Mello Yello | |
|---|---|---|
| Caffeine per serving | 38mg per 12 oz can | 51mg per 12 oz can |
| Caffeine per fl oz | 3.2mg | 4.2mg |
| Servings to reach 400mg (FDA context) | 10.5 | 7.8 |
Sources: Pepsi's figure is verified in our Pepsi caffeine guide against Caffeine Informer (source); Mello Yello's figure is verified in our Mello Yello guide against Caffeine Informer (source).
Which one should you pick?
Pick Pepsi when you want the lighter dose or a slower ramp, and Mello Yello 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
- Pepsi: the full caffeine guide
- Mello Yello: the full caffeine guide
- The verified caffeine database
- Every drink compared: the comparisons index
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FAQ
Does Pepsi or Mello Yello have more caffeine? Mello Yello: 51mg per 12 oz can versus 38mg per 12 oz can for Pepsi.
Which is stronger per ounce? Mello Yello, at about 4.2mg per fluid ounce versus 3.2mg for Pepsi.
Comparing caffeine? The caffeine comparison tool puts hundreds of drinks side by side, and the caffeine curfew calculator can check your cutoff time for tonight.
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