Reign Storm has more caffeine than ZOA: 200mg vs 160mg in the same 12 oz can. That is a 40mg gap, and since the cans match, the per-serving number is the whole story.
ZOA vs Reign Storm: the numbers
| ZOA | Reign Storm | |
|---|---|---|
| Caffeine per serving | 160mg per 12 oz can | 200mg per 12 oz can |
| Caffeine per fl oz | 13.3mg | 16.7mg |
| Servings to reach 400mg (FDA context) | 2.5 | 2.0 |
Sources: ZOA's figure is verified in our ZOA caffeine guide against ZOA FAQ (source); Reign Storm's figure is verified in our Reign Storm guide against Caffeine Informer (source).
Which one should you pick?
Pick ZOA when you want the lighter dose or a slower ramp, and Reign Storm 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
- ZOA: the full caffeine guide
- Reign Storm: the full caffeine guide
- The verified caffeine database
- Every drink compared: the comparisons index
FAQ
Does ZOA or Reign Storm have more caffeine? Reign Storm: 200mg per 12 oz can versus 160mg per 12 oz can for ZOA.
Which is stronger per ounce? Reign Storm, at about 16.7mg per fluid ounce versus 13.3mg for ZOA.
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.