How much caffeine is in C4 Original (1 scoop)?

A single 300 ml serving of C4 Original prepared from one scoop contains 150 mg of caffeine. That works out to a concentration of 50 mg per 100 ml, which is roughly double the density of a typical drip coffee. The dose sits squarely in the moderate-to-high zone for a pre-workout supplement, delivering the caffeine equivalent of about one and a half standard cups of drip coffee in a single drink. Most people will feel the first perceptible lift within 15 to 30 minutes of finishing the serving, as the caffeine is absorbed through the small intestine and plasma concentrations begin to climb toward a peak that typically lands 30 to 60 minutes after ingestion, aligning with the start of a training session.

At 150 mg, this dose is large enough to produce measurable effects on alertness, perceived exertion and reaction time in most healthy adults who are not habituated to very high daily intakes. The FDA cites 400 mg as the daily limit not generally associated with dangerous, negative effects in healthy adults, which means this single serving uses 38% of that ceiling. For someone who consumes little caffeine otherwise, 150 mg can feel quite strong; for a habitual coffee drinker who already has two or three cups before noon, the same dose may register as a familiar bump rather than a jolt. The experience is shaped by body mass, liver enzyme activity and adenosine receptor sensitivity, all of which vary widely across individuals.

How long C4 Original (1 scoop) stays in your system

Caffeine follows first-order elimination kinetics with a population-average half-life of 5.7 hours, meaning that every 5.7 hours the body clears roughly half of the caffeine still circulating. Starting from a 150 mg dose, the arithmetic runs as follows: after 3 hours the remaining caffeine is approximately 150 × 0.5^(3 / 5.7) ≈ 104 mg; after 6 hours it drops to 150 × 0.5^(6 / 5.7) ≈ 72 mg; after 9 hours it falls to roughly 50 mg; and after 12 hours about 35 mg remains. These are central estimates for a healthy adult liver; individual clearance rates can be 30–50% faster in smokers or substantially slower in people taking oral contraceptives or during the third trimester of pregnancy, where the half-life can extend beyond 10 hours.

What this decay curve means in practical terms is that a C4 Original consumed at 15:00 still leaves roughly 72 mg of caffeine active in the bloodstream at 21:00. That is more caffeine than a full 250 ml can of Red Bull, which contains 80 mg total. For someone aiming to be asleep by 23:00, the residual at bedtime would be around 50 mg, a quantity that the 2013 study by Drake et al. published in the Journal of Clinical Sleep Medicine suggests is enough to measurably disrupt sleep architecture even when the person does not consciously feel wired. The caffeine half-life calculator lets you model this curve with your own dosing time and a custom half-life if you know your CYP1A2 status.

Because a single serving of C4 Original uses 38% of the FDA’s 400 mg daily ceiling, a healthy adult could theoretically consume two full scoops across a day—totalling 300 mg—and still remain under the limit, provided no other caffeine sources are added. A third scoop would push the total to 450 mg, exceeding the guidance and entering the zone where the EFSA’s 2015 Scientific Opinion on the Safety of Caffeine flags an increased likelihood of transient anxiety, tachycardia and sleep disturbance. For most people, limiting intake to one serving per day leaves ample room for a morning coffee or an afternoon tea without crossing the 400 mg threshold.

Sleep timing is the more sensitive constraint for many users. Using the population-average half-life of 5.7 hours, a 150 mg dose consumed at 17:00 leaves roughly 72 mg still active at 23:00, a quantity that the Drake et al. 2013 study shows can reduce total sleep time and increase wake after sleep onset even when the subject does not perceive the disruption. To keep the bedtime residual below 30 mg—a level at which sleep impact is minimal for most adults—the latest cup before bedtime calculator suggests finishing the drink no later than 14:00 for a 23:00 lights-out. Pregnant individuals are advised by the EFSA to limit total daily caffeine to 200 mg, which means a single C4 Original already occupies 75% of that allowance; a second serving would breach it outright. Adolescents, who have a lower body mass on average and a developing nervous system, should stay well below the adult 400 mg figure, and Health Canada’s guidance of 2.5 mg per kg of body weight per day would place a 60 kg teenager’s limit at 150 mg—exactly this one serving, with no margin for any other source.

Within the pre-workout category, C4 Original at 150 mg per serving occupies the middle ground. It sits below the 200 mg single-scoop pre-workouts that have become common in the category, and well below the 300 mg formulations aimed at experienced users. For comparison, a standard Pre-workout (1 scoop) at 200 mg delivers 33% more caffeine in the same 300 ml volume, while a single caffeine pill (200 mg) provides a larger bolus with zero liquid. On the lower end, a 100 mg caffeine pill offers two-thirds of the C4 dose, and a piece of caffeine gum (40 mg) is a fraction of the amount, absorbed more rapidly through the buccal mucosa but with a shorter duration of effect.

Measured against everyday coffee benchmarks, 150 mg is equivalent to roughly 1.6 cups of drip coffee, where a standard 240 ml cup is assigned 96 mg based on USDA FoodData Central averages. It outpaces a single espresso shot (63 mg) by a factor of 2.4, exceeds a 250 ml Red Bull (80 mg) by nearly double, and lands just under a full 473 ml can of Monster Energy (160 mg). Compared with a 240 ml cup of green tea, which averages 28 mg, the C4 Original serving contains more than five times the caffeine. This places the drink firmly in the territory of intentional stimulation rather than background consumption, and the side-by-side drink comparison tool makes it easy to stack it against any other beverage in the dataset.

What changes the number for C4 Original (1 scoop)

The 150 mg figure on this page represents C4 Original prepared exactly as directed: one level scoop mixed into 300 ml of water. The actual caffeine content in a real-world serving can drift for several reasons. First, scoop density matters; a heaped scoop can easily deliver 10–15% more powder by mass, pushing the caffeine closer to 170 mg, while an underfilled scoop might drop it to 130 mg. Second, the manufacturer’s own specification is a nominal value, and batch-to-batch variation in raw caffeine anhydrous is generally small—typically within ±5% of the label claim for a major brand—but not zero. Third, some users deliberately split a scoop across two smaller drinks, which halves the dose to roughly 75 mg per serving, while others double-scoop for a 300 mg load that already occupies 75% of the FDA’s 400 mg daily guidance in a single sitting.

Beyond the Original formula, the C4 line includes several variants with meaningfully different caffeine profiles. C4 Ultimate, for example, is built around a 300 mg dose per serving, double the Original. C4 Sport sits at a lower 135 mg per scoop, while C4 Smart Energy cans deliver 200 mg in a 473 ml format. There is no commercially available decaffeinated version of C4 Original, so anyone seeking a stimulant-free pre-workout must switch to a different product altogether. The numbers on this page are drawn from the manufacturer’s published label for the Original variant sold in the United States; international formulations sometimes differ because of local regulatory caps on caffeine per serving.

Temperature and storage also play a minor role. Caffeine anhydrous is a stable molecule, but prolonged exposure to high humidity can cause clumping that affects scoop uniformity. For the most consistent dosing, the container should be kept tightly sealed in a cool, dry place and the scoop should be levelled rather than tamped. Even with perfect technique, the figure on the label is best understood as the centre of a narrow range—call it 140–160 mg for a careful single scoop—rather than a certified analytical value for every glass.

Where this figure comes from

The 150 mg value on this page is taken directly from the manufacturer’s published supplement facts panel for C4 Original, which lists caffeine anhydrous as a declared ingredient with a quantified amount per serving. Where the manufacturer’s label is clear and the product is sold in a regulated market, we treat that figure as the primary source. Independent laboratory verification of pre-workout caffeine content is relatively sparse in the peer-reviewed literature, but the few published assays—such as those conducted by consumer-protection labs and reported in the Journal of Analytical Toxicology—generally find that major commercial pre-workouts fall within 10% of their label claims for caffeine. We cross-reference against the USDA FoodData Central database for coffee and tea benchmarks, and against the EFSA and FDA guidance documents for safety thresholds, all of which are linked in the references.

Published values for the same product can disagree when a manufacturer reformulates without changing the product name, when an international version carries a different caffeine load, or when a third-party database scrapes an outdated label. We update our figure when the manufacturer issues a new label with a verified change, when a credible laboratory analysis demonstrates a systematic deviation, or when a regulatory authority publishes a revised assessment. The open caffeine dataset behind these pages logs every revision so that the provenance of the number is always traceable.

Bottom line

C4 Original mixed from one level scoop into 300 ml of water delivers 150 mg of caffeine, which is equivalent to roughly 1.6 cups of drip coffee and represents 38% of the FDA’s 400 mg daily guidance for healthy adults. The dose peaks in the bloodstream around 30 to 60 minutes after ingestion and declines with a half-life of 5.7 hours, leaving approximately 72 mg still circulating after six hours. A single serving fits inside the daily limit for most people, but timing matters: to keep the bedtime residual low enough to protect sleep, the drink is best finished at least nine hours before lights-out. Pregnant individuals, adolescents and anyone with a known sensitivity should treat this as a substantial dose that leaves little room for additional caffeine on the same day.