C4 Ultimate Energy vs 5-hour Energy (regular): which has more caffeine?

C4 Ultimate Energy carries more total caffeine per serving (300mg per 16 oz can vs 200mg per 1.93 oz shot), but ounce for ounce 5-hour Energy (regular) is actually the stronger drink at about 104mg per fluid ounce against 19. Which one "has more caffeine" depends on whether you measure the container or the concentration.

C4 Ultimate Energy vs 5-hour Energy (regular): the numbers

Sources: C4 Ultimate Energy's figure is verified in our C4 Ultimate Energy caffeine guide against Caffeine Informer (source); 5-hour Energy (regular)'s figure is verified in our 5-hour Energy (regular) guide against 5-hour Energy facts page (source).

The concentration gap is the striking part: 5-hour Energy (regular) packs roughly 6 times the caffeine per ounce. Sipping speed matters at that density; a 1.93 oz shot finished in minutes hits differently than the same milligrams spread over a slow cup.

Which one should you pick?

Pick 5-hour Energy (regular) 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
• 5-hour Energy (regular): the full caffeine guide
• The verified caffeine database
• Every drink compared: the comparisons index
• Compare any two of 120+ drinks

FAQ

Does C4 Ultimate Energy or 5-hour Energy (regular) have more caffeine? C4 Ultimate Energy: 300mg per 16 oz can versus 200mg per 1.93 oz shot for 5-hour Energy (regular).

Which is stronger per ounce? 5-hour Energy (regular), at about 103.6mg per fluid ounce versus 18.8mg for C4 Ultimate Energy.