Rockstar Original has more caffeine than Red Bull on both counts: 160mg per 16 oz can against 80mg per 8.4 oz can, and about 10mg per fluid ounce against 10. The serving sizes differ, so the table below shows both ways of counting.
Red Bull vs Rockstar Original: the numbers
| Red Bull | Rockstar Original | |
|---|---|---|
| Caffeine per serving | 80mg per 8.4 oz can | 160mg per 16 oz can |
| Caffeine per fl oz | 9.5mg | 10.0mg |
| Servings to reach 400mg (FDA context) | 5.0 | 2.5 |
Sources: Red Bull's figure is verified in our Red Bull caffeine guide against Red Bull label / Caffeine Informer (source); Rockstar Original's figure is verified in our Rockstar Original guide against Rockstar product page (source).
Which one should you pick?
Pick Red Bull when you want the lighter dose or a slower ramp, and Rockstar Original 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
- Rockstar Original: the full caffeine guide
- The verified caffeine database
- Every drink compared: the comparisons index
FAQ
Does Red Bull or Rockstar Original have more caffeine? Rockstar Original: 160mg per 16 oz can versus 80mg per 8.4 oz can for Red Bull.
Which is stronger per ounce? Rockstar Original, at about 10.0mg per fluid ounce versus 9.5mg for Red Bull.
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.