Starbucks bottled Frappuccino (Mocha) carries more total caffeine per serving (105mg per 13.7 oz bottle 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 8. 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.
Red Bull vs Starbucks bottled Frappuccino (Mocha): the numbers
| Red Bull | Starbucks bottled Frappuccino (Mocha) | |
|---|---|---|
| Caffeine per serving | 80mg per 8.4 oz can | 105mg per 13.7 oz bottle |
| Caffeine per fl oz | 9.5mg | 7.7mg |
| Servings to reach 400mg (FDA context) | 5.0 | 3.8 |
Sources: Red Bull's figure is verified in our Red Bull caffeine guide against Red Bull label / Caffeine Informer (source); Starbucks bottled Frappuccino (Mocha)'s figure is verified in our Starbucks bottled Frappuccino (Mocha) guide against PepsiCo product facts (source).
Which one should you pick?
Pick Red Bull when you want the lighter dose or a slower ramp, and Starbucks bottled Frappuccino (Mocha) 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
- Red Bull: the full caffeine guide
- Starbucks bottled Frappuccino (Mocha): the full caffeine guide
- The verified caffeine database
- Every drink compared: the comparisons index
FAQ
Does Red Bull or Starbucks bottled Frappuccino (Mocha) have more caffeine? Starbucks bottled Frappuccino (Mocha): 105mg per 13.7 oz bottle 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 7.7mg for Starbucks bottled Frappuccino (Mocha).
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.