C4 Ultimate Energy has more caffeine than Monster: 300mg vs 160mg in the same 16 oz can. That is a 140mg gap, and since the cans match, the per-serving number is the whole story.
C4 Ultimate Energy vs Monster: the numbers
| C4 Ultimate Energy | Monster | |
|---|---|---|
| Caffeine per serving | 300mg per 16 oz can | 160mg per 16 oz can |
| Caffeine per fl oz | 18.8mg | 10.0mg |
| Servings to reach 400mg (FDA context) | 1.3 | 2.5 |
Sources: C4 Ultimate Energy's figure is verified in our C4 Ultimate Energy caffeine guide against Caffeine Informer (source); Monster's figure is verified in our Monster guide against Caffeine Informer (source).
Which one should you pick?
Pick Monster when you want the lighter dose or a slower ramp, and C4 Ultimate 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
- C4 Ultimate Energy: the full caffeine guide
- Monster: 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 C4 Ultimate Energy or Monster have more caffeine? C4 Ultimate Energy: 300mg per 16 oz can versus 160mg per 16 oz can for Monster.
Which is stronger per ounce? C4 Ultimate Energy, at about 18.8mg per fluid ounce versus 10.0mg for Monster.
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