Rockstar Original has more caffeine than Water Joe (caffeinated water) on both counts: 160mg per 16 oz can against 70mg per 16.9 oz bottle, and about 10mg per fluid ounce against 4. The serving sizes differ, so the table below shows both ways of counting.
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.
Water Joe (caffeinated water) vs Rockstar Original: the numbers
| Water Joe (caffeinated water) | Rockstar Original | |
|---|---|---|
| Caffeine per serving | 70mg per 16.9 oz bottle | 160mg per 16 oz can |
| Caffeine per fl oz | 4.1mg | 10.0mg |
| Servings to reach 400mg (FDA context) | 5.7 | 2.5 |
Sources: Water Joe (caffeinated water)'s figure is verified in our Water Joe (caffeinated water) caffeine guide against Water Joe / 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 Water Joe (caffeinated water) 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
- Water Joe (caffeinated water): 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 Water Joe (caffeinated water) or Rockstar Original have more caffeine? Rockstar Original: 160mg per 16 oz can versus 70mg per 16.9 oz bottle for Water Joe (caffeinated water).
Which is stronger per ounce? Rockstar Original, at about 10.0mg per fluid ounce versus 4.1mg for Water Joe (caffeinated water).
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