Tools Writing · 19 August 2026 · By Cristian Cojocaru

C4 pre-workout: what the label actually says

We scanned the best-selling pre-workout in the world and it came back 64. Caffeine at 150mg is the only ingredient in it at a researched dose, and all five vitamins on the front land under the daily value.

C4 Original is the pre-workout most people buy first. It's cheap, it's in every supermarket and every gym shop, and it has thousands of reviews.

We scanned the supplement facts panel. Here's what one scoop actually contains.

One ingredient is at a researched dose

Caffeine, at 150mg. That's a real ergogenic dose and it's the one thing in the tub doing what the tub says.

150mg is also about a large coffee. Which is worth sitting with, because it's the active half of a £21 product.

Beta-alanine at 1600mg is the second best thing on the label, and it's at the very bottom of the studied range. Research uses 3.2g to 6.4g daily, so you're at half the floor.

It'll still make you tingle, because the tingle starts around 800mg and has nothing to do with the dose working.

Everything else is a fraction

Creatine at 1500mg is under a third of a maintenance dose, and creatine is the single best-evidenced ingredient in sports nutrition. It's there in a quantity that can't do the thing it's famous for.

Tyrosine at 200mg is a tenth of where the research starts. Arginine at 1000mg is below the range where trials disagree about whether it works at all, and oral arginine is poorly absorbed on top of that.

The vitamins are the part nobody checks

This is the bit that surprised us.

Every one is below the daily value. Not below a research dose, below the basic labelling figure meant to cover an ordinary adult.

Niacin is at 15% of it. B6 is at 29%. These aren't performance doses and they aren't topping you up either. They're there so the panel has more lines on it.

What it costs to get 150mg of caffeine

Eight of the ten ingredients are below a researched dose or unsupported, so most of what you're paying for isn't doing the job it's on the label for. That works out at around $204 a year.

Caffeine tablets cost a few pounds for a hundred of them.

So is it worth it?

If what you want is a stimulant before training, it works, and 150mg is a sensible amount rather than the 400mg some products push you to.

If you believed you were also getting creatine, a pump ingredient, a nootropic and a B-complex, you're getting gestures at all four. The label is accurate and nothing on it is a lie. It's just that reading it tells you almost nothing unless you already know what dose each thing needs.

That's the whole reason we built the thing that reads it.

What to do

1. Find the caffeine line and stop there. At 150mg it is the one ingredient doing what the label implies, and it is the only number worth comparing between pre-workouts at this price.
2. Treat the rest as a list, not a formula. Creatine, beta-alanine and the nootropic are all present at fractions of their researched amounts.
3. Check the vitamins against what you already take. All five land under the daily value here, so they stack with a multivitamin rather than replacing it.

Related reading: ABE pre-workout: what the label actually says, Gold Standard pre-workout: what the label actually says and Gorilla Mode pre-workout: what the label actually says.

Verdict does the arithmetic automatically. Photograph the supplement facts panel and it reads every dose off the label, compares each against the amount used in published research, and adds the totals across everything you take. It reports the arithmetic and names the source of every figure. It doesn't tell you what to take.