C4 Performance Energy has more caffeine than Rockstar Original: 200mg vs 160mg in the same 16 oz can. That is a 40mg gap, and since the cans match, the per-serving number is the whole story.
Rockstar Original vs C4 Performance Energy: the numbers
| Rockstar Original | C4 Performance Energy | |
|---|---|---|
| Caffeine per serving | 160mg per 16 oz can | 200mg per 16 oz can |
| Caffeine per fl oz | 10.0mg | 12.5mg |
| Servings to reach 400mg (FDA context) | 2.5 | 2.0 |
Sources: Rockstar Original's figure is verified in our Rockstar Original caffeine guide against Rockstar product page (source); C4 Performance Energy's figure is verified in our C4 Performance Energy guide against Caffeine Informer (source).
Which one should you pick?
Pick Rockstar Original when you want the lighter dose or a slower ramp, and C4 Performance Energy 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
- Rockstar Original: the full caffeine guide
- C4 Performance Energy: the full caffeine guide
- The verified caffeine database
- Every drink compared: the comparisons index
FAQ
Does Rockstar Original or C4 Performance Energy have more caffeine? C4 Performance Energy: 200mg per 16 oz can versus 160mg per 16 oz can for Rockstar Original.
Which is stronger per ounce? C4 Performance Energy, at about 12.5mg per fluid ounce versus 10.0mg for Rockstar Original.
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.