Dunkin iced coffee (medium) has more caffeine than McDonald's iced coffee on both counts: 297mg per 24 oz medium against 133mg per 11.5 oz medium, and about 12mg per fluid ounce against 12. The serving sizes differ, so the table below shows both ways of counting.
McDonald's iced coffee vs Dunkin iced coffee (medium): the numbers
| McDonald's iced coffee | Dunkin iced coffee (medium) | |
|---|---|---|
| Caffeine per serving | 133mg per 11.5 oz medium | 297mg per 24 oz medium |
| Caffeine per fl oz | 11.6mg | 12.4mg |
| Servings to reach 400mg (FDA context) | 3.0 | 1.3 |
Sources: McDonald's iced coffee's figure is verified in our McDonald's iced coffee caffeine guide against Caffeine Informer (source); Dunkin iced coffee (medium)'s figure is verified in our Dunkin iced coffee (medium) guide against Caffeine Informer Dunkin guide (source).
Which one should you pick?
Pick McDonald's iced coffee when you want the lighter dose or a slower ramp, and Dunkin iced coffee (medium) 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
- McDonald's iced coffee: the full caffeine guide
- Dunkin iced coffee (medium): the full caffeine guide
- The verified caffeine database
- Every drink compared: the comparisons index
- Compare any two of 120+ drinks
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Gear from this guide
FAQ
Does McDonald's iced coffee or Dunkin iced coffee (medium) have more caffeine? Dunkin iced coffee (medium): 297mg per 24 oz medium versus 133mg per 11.5 oz medium for McDonald's iced coffee.
Which is stronger per ounce? Dunkin iced coffee (medium), at about 12.4mg per fluid ounce versus 11.6mg for McDonald's iced coffee.
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