McDonald's Sweet Tea (large) carries more total caffeine per serving (100mg per 32 oz cup vs 80mg per 8.4 oz can), but ounce for ounce Red Bull is actually the stronger drink at about 10mg per fluid ounce against 3. Which one "has more caffeine" depends on whether you measure the container or the concentration.
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.
McDonald's Sweet Tea (large) vs Red Bull: the numbers
| McDonald's Sweet Tea (large) | Red Bull | |
|---|---|---|
| Caffeine per serving | 100mg per 32 oz cup | 80mg per 8.4 oz can |
| Caffeine per fl oz | 3.1mg | 9.5mg |
| Servings to reach 400mg (FDA context) | 4.0 | 5.0 |
Sources: McDonald's Sweet Tea (large)'s figure is verified in our McDonald's Sweet Tea (large) caffeine guide against Caffeine Informer (source); Red Bull's figure is verified in our Red Bull guide against Red Bull label / Caffeine Informer (source).
The concentration gap is the striking part: Red Bull packs roughly 3 times the caffeine per ounce. Sipping speed matters at that density; a 8.4 oz can finished in minutes hits differently than the same milligrams spread over a slow cup.
Which one should you pick?
Pick Red Bull when you want the lighter dose or a slower ramp, and McDonald's Sweet Tea (large) 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 Sweet Tea (large): the full caffeine guide
- Red Bull: 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 Sweet Tea (large) or Red Bull have more caffeine? McDonald's Sweet Tea (large): 100mg per 32 oz cup versus 80mg per 8.4 oz can for Red Bull.
Which is stronger per ounce? Red Bull, at about 9.5mg per fluid ounce versus 3.1mg for McDonald's Sweet Tea (large).
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