C4 Performance Energy has more caffeine than Monster Ultra (Zero Ultra): 200mg vs 150mg in the same 16 oz can. That is a 50mg gap, and since the cans match, the per-serving number is the whole story.
Monster Ultra (Zero Ultra) vs C4 Performance Energy: the numbers
| Monster Ultra (Zero Ultra) | C4 Performance Energy | |
|---|---|---|
| Caffeine per serving | 150mg per 16 oz can | 200mg per 16 oz can |
| Caffeine per fl oz | 9.4mg | 12.5mg |
| Servings to reach 400mg (FDA context) | 2.7 | 2.0 |
Sources: Monster Ultra (Zero Ultra)'s figure is verified in our Monster Ultra (Zero Ultra) caffeine guide against Caffeine Informer (source); C4 Performance Energy's figure is verified in our C4 Performance Energy guide against Caffeine Informer (source).
Which one should you pick?
Pick Monster Ultra (Zero Ultra) 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
- Monster Ultra (Zero Ultra): the full caffeine guide
- C4 Performance Energy: the full caffeine guide
- The verified caffeine database
- Every drink compared: the comparisons index
- Compare any two of 120+ drinks
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Gear from this guide
FAQ
Does Monster Ultra (Zero Ultra) or C4 Performance Energy have more caffeine? C4 Performance Energy: 200mg per 16 oz can versus 150mg per 16 oz can for Monster Ultra (Zero Ultra).
Which is stronger per ounce? C4 Performance Energy, at about 12.5mg per fluid ounce versus 9.4mg for Monster Ultra (Zero Ultra).
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