XS Energy vs C4 Performance Energy: which has more caffeine?

C4 Performance Energy has more caffeine than XS Energy on both counts: 200mg per 16 oz can against 80mg per 8.4 oz can, and about 12mg per fluid ounce against 10. The serving sizes differ, so the table below shows both ways of counting.

XS Energy vs C4 Performance Energy: the numbers

Sources: XS Energy's figure is verified in our XS Energy 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 XS Energy 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

• XS Energy: 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 XS Energy or C4 Performance Energy have more caffeine? C4 Performance Energy: 200mg per 16 oz can versus 80mg per 8.4 oz can for XS Energy.

Which is stronger per ounce? C4 Performance Energy, at about 12.5mg per fluid ounce versus 9.5mg for XS Energy.