C4 Performance Energy carries more total caffeine per serving (200mg per 16 oz can vs 155mg per 9.6 oz can), but ounce for ounce Starbucks canned Nitro (Black) is actually the stronger drink at about 16mg per fluid ounce against 12. Which one "has more caffeine" depends on whether you measure the container or the concentration.
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.
Starbucks canned Nitro (Black) vs C4 Performance Energy: the numbers
| Starbucks canned Nitro (Black) | C4 Performance Energy | |
|---|---|---|
| Caffeine per serving | 155mg per 9.6 oz can | 200mg per 16 oz can |
| Caffeine per fl oz | 16.1mg | 12.5mg |
| Servings to reach 400mg (FDA context) | 2.6 | 2.0 |
Sources: Starbucks canned Nitro (Black)'s figure is verified in our Starbucks canned Nitro (Black) caffeine guide against PepsiCo product facts (source); C4 Performance Energy's figure is verified in our C4 Performance Energy guide against Caffeine Informer (source).
Which one should you pick?
Pick Starbucks canned Nitro (Black) 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
- Starbucks canned Nitro (Black): the full caffeine guide
- C4 Performance Energy: the full caffeine guide
- The verified caffeine database
- Every drink compared: the comparisons index
FAQ
Does Starbucks canned Nitro (Black) or C4 Performance Energy have more caffeine? C4 Performance Energy: 200mg per 16 oz can versus 155mg per 9.6 oz can for Starbucks canned Nitro (Black).
Which is stronger per ounce? Starbucks canned Nitro (Black), at about 16.1mg per fluid ounce versus 12.5mg for C4 Performance 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.