C4, the popular pre-workout supplement from Cellucor, contains a core set of performance ingredients: 200mg of caffeine, 2 grams of beta-alanine, creatine nitrate, and L-citrulline, along with artificial sweeteners and B vitamins. The exact formula varies depending on which version you pick up, since C4 now spans powders, canned energy drinks, and sport-certified lines.
Caffeine: The Main Energy Driver
Every version of C4 relies on caffeine as its primary energy source. The original powder and the 12-ounce canned drinks contain 200mg per serving, roughly equivalent to two cups of brewed coffee. The C4 Ultimate line bumps that up to 300mg in a 16-ounce can. If you’re sensitive to caffeine or already drink coffee in the morning, that 200mg floor is worth keeping in mind before you stack another source on top of it.
Beta-Alanine and the Tingling Sensation
C4 Original contains 2 grams of CarnoSyn beta-alanine per serving. Beta-alanine is an amino acid that your body uses to build carnosine, a compound stored in muscles that helps buffer acid buildup during intense exercise. The practical result is that your muscles can work a bit longer before that deep burning feeling forces you to stop a set.
The tingling or prickling sensation many people feel on their skin after taking C4, especially around the face, neck, and hands, comes directly from beta-alanine. It’s harmless and temporary, typically fading within 30 to 60 minutes. Higher doses make the tingling more noticeable. Research supports beta-alanine doses ranging from 1.6 to 6.4 grams daily, so C4’s 2-gram serving sits at the lower end of that studied range.
Creatine Nitrate
Rather than using standard creatine monohydrate, C4 uses creatine nitrate, a form that bonds creatine with a nitrate molecule. The creatine half supports short-burst strength and power output the way any creatine does. The nitrate half converts into nitric oxide in your body, which relaxes blood vessels and improves blood flow to working muscles. This can reduce how much oxygen your muscles need during exercise and improve overall exercise tolerance. It’s a two-in-one ingredient designed to cover both strength support and the “pump” feeling people look for in a pre-workout.
L-Citrulline and Other Amino Acids
The canned energy drink version lists L-citrulline as a key ingredient. Like the nitrate in creatine nitrate, citrulline supports nitric oxide production and blood flow. It’s one of the most common pump-focused ingredients in pre-workouts. C4 also includes N-acetyl-L-tyrosine, an amino acid that supports the production of brain chemicals involved in focus and alertness, complementing the stimulant effect of caffeine.
The Sport version, designed for tested athletes, swaps in betaine anhydrous (listed as BetaPower on the label). Betaine is a compound found naturally in beets and spinach that has been studied for its effects on strength and power output.
Sweeteners, Vitamins, and Other Additives
C4 gets its sweet taste without calories by using two artificial sweeteners: sucralose and acesulfame potassium. These are the same sweeteners found in many diet sodas and zero-calorie drinks. The canned version also contains carbonated water, malic acid, citric acid, natural flavors, and potassium sorbate as a preservative.
On the vitamin side, C4 includes niacinamide (a form of vitamin B3) and cyanocobalamin (vitamin B12). B vitamins play a role in energy metabolism, helping your body convert food into usable fuel. They won’t give you a noticeable energy boost on their own, but they round out the formula. Notably, C4’s ingredient lists don’t include artificial food dyes, which sets it apart from some competing pre-workouts.
How Ingredients Differ Across C4 Versions
The C4 lineup has expanded well beyond the original powder, and the ingredient profiles shift meaningfully between versions. C4 Original is the baseline formula with 200mg caffeine and 2 grams of beta-alanine. C4 Ultimate pushes caffeine to 300mg and generally includes higher doses of performance ingredients. C4 Sport is built for competitive athletes and carries NSF Certified for Sport status, meaning every batch is tested for over 290 banned substances and manufactured in audited, GMP-compliant facilities. If you’re subject to drug testing in your sport, the Sport or Performance Energy lines are the ones designed with that in mind.
The canned energy drinks (C4 Energy, C4 Smart Energy, C4 Performance Energy) deliver similar core ingredients in a ready-to-drink format but tend to emphasize convenience over maximal dosing. If you’re comparing labels, pay attention to the per-serving amounts rather than assuming every C4 product delivers the same formula.