Celsius has more caffeine than Rockstar Original on both counts: 200mg per 12 oz can against 160mg per 16 oz can, and about 17mg per fluid ounce against 10. The serving sizes differ, so the table below shows both ways of counting.
Celsius vs Rockstar Original: the numbers
| Celsius | Rockstar Original | |
|---|---|---|
| Caffeine per serving | 200mg per 12 oz can | 160mg per 16 oz can |
| Caffeine per fl oz | 16.7mg | 10.0mg |
| Servings to reach 400mg (FDA context) | 2.0 | 2.5 |
Sources: Celsius's figure is verified in our Celsius caffeine guide against Celsius essential facts (source); Rockstar Original's figure is verified in our Rockstar Original guide against Rockstar product page (source).
Which one should you pick?
Pick Rockstar Original when you want the lighter dose or a slower ramp, and Celsius 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
- Celsius: the full caffeine guide
- Rockstar Original: the full caffeine guide
- The verified caffeine database
- Every drink compared: the comparisons index
FAQ
Does Celsius or Rockstar Original have more caffeine? Celsius: 200mg per 12 oz can versus 160mg per 16 oz can for Rockstar Original.
Which is stronger per ounce? Celsius, at about 16.7mg 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.