International Delight iced coffee has more caffeine than Diet Pepsi: 88mg vs 35mg in the same 12 oz serving. That is a 53mg gap, and since the cans match, the per-serving number is the whole story.
These are different categories of drink, which changes how the caffeine arrives. Energy drinks and sodas list an exact number because caffeine is a measured additive; brewed drinks vary with the beans and the brew, so their figures are compiled averages. The numbers here are the standard published values for each.
Diet Pepsi vs International Delight iced coffee: the numbers
| Diet Pepsi | International Delight iced coffee | |
|---|---|---|
| Caffeine per serving | 35mg per 12 oz can | 88mg per 12 oz serving |
| Caffeine per fl oz | 2.9mg | 7.3mg |
| Servings to reach 400mg (FDA context) | 11.4 | 4.5 |
Sources: Diet Pepsi's figure is verified in our Diet Pepsi caffeine guide against Caffeine Informer (source); International Delight iced coffee's figure is verified in our International Delight iced coffee guide against Caffeine Informer (source).
Which one should you pick?
Pick Diet Pepsi when you want the lighter dose or a slower ramp, and International Delight iced coffee 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 Pepsi: the full caffeine guide
- International Delight iced coffee: the full caffeine guide
- The verified caffeine database
FAQ
Does Diet Pepsi or International Delight iced coffee have more caffeine? International Delight iced coffee: 88mg per 12 oz serving versus 35mg per 12 oz can for Diet Pepsi.
Which is stronger per ounce? International Delight iced coffee, at about 7.3mg per fluid ounce versus 2.9mg for Diet 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.