Rockstar Original has more caffeine than Guayaki Yerba Mate (can) on both counts: 160mg per 16 oz can against 150mg per 15.5 oz can, and about 10mg per fluid ounce against 10. The serving sizes differ, so the table below shows both ways of counting.
Guayaki Yerba Mate (can) vs Rockstar Original: the numbers
| Guayaki Yerba Mate (can) | Rockstar Original | |
|---|---|---|
| Caffeine per serving | 150mg per 15.5 oz can | 160mg per 16 oz can |
| Caffeine per fl oz | 9.7mg | 10.0mg |
| Servings to reach 400mg (FDA context) | 2.7 | 2.5 |
Sources: Guayaki Yerba Mate (can)'s figure is verified in our Guayaki Yerba Mate (can) caffeine guide against Guayaki product page (source); Rockstar Original's figure is verified in our Rockstar Original guide against Rockstar product page (source).
Which one should you pick?
Pick Guayaki Yerba Mate (can) 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
- Guayaki Yerba Mate (can): the full caffeine guide
- Rockstar Original: the full caffeine guide
- The verified caffeine database
- Every drink compared: the comparisons index
- Compare any two of 120+ drinks
FAQ
Does Guayaki Yerba Mate (can) or Rockstar Original have more caffeine? Rockstar Original: 160mg per 16 oz can versus 150mg per 15.5 oz can for Guayaki Yerba Mate (can).
Which is stronger per ounce? Rockstar Original, at about 10.0mg per fluid ounce versus 9.7mg for Guayaki Yerba Mate (can).
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