C4 Smart Energy and Java Monster list the same 200mg of caffeine per can, but the cans differ: 16 oz for C4 Smart Energy against 15 oz for Java Monster, so ounce for ounce Java Monster is slightly stronger at about 13mg per fluid ounce against 12. Which one "has more caffeine" depends on whether you measure the container or the concentration.
C4 Smart Energy vs Java Monster: the numbers
| C4 Smart Energy | Java Monster | |
|---|---|---|
| Caffeine per serving | 200mg per 16 oz can | 200mg per 15 oz can |
| Caffeine per fl oz | 12.5mg | 13.3mg |
| Servings to reach 400mg (FDA context) | 2.0 | 2.0 |
Sources: C4 Smart Energy's figure is verified in our C4 Smart Energy caffeine guide against Cellucor / Caffeine Informer (source); Java Monster's figure is verified in our Java Monster guide against Caffeine Informer (source).
Which one should you pick?
Per can the dose is identical, so pick on everything besides the caffeine number: Java Monster is a non-carbonated coffee and milk drink, while C4 Smart Energy is a conventional energy drink formula. 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 Smart Energy: the full caffeine guide
- Java 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 Smart Energy or Java Monster have more caffeine? They tie on the label: 200mg per 16 oz can for C4 Smart Energy and 200mg per 15 oz can for Java Monster. The smaller can makes Java Monster slightly stronger per ounce.
Which is stronger per ounce? Java Monster, at about 13.3mg per fluid ounce versus 12.5mg for C4 Smart Energy.
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.
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