Starbucks Flat White vs C4 Performance Energy: which has more caffeine?

C4 Performance Energy has more caffeine than Starbucks Flat White: 200mg vs 195mg in the same 16 oz can. That is a 5mg gap, and since the cans match, the per-serving number is the whole story.

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 Flat White vs C4 Performance Energy: the numbers

Sources: Starbucks Flat White's figure is verified in our Starbucks Flat White caffeine guide against Starbucks nutrition listing (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 Flat White 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 Flat White: 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

FAQ

Does Starbucks Flat White or C4 Performance Energy have more caffeine? C4 Performance Energy: 200mg per 16 oz can versus 195mg per 16 oz grande for Starbucks Flat White.

Which is stronger per ounce? C4 Performance Energy, at about 12.5mg per fluid ounce versus 12.2mg for Starbucks Flat White.