What “€ per 100 g of protein” actually means, and why most price comparisons get it wrong
Price per tub, per kilo of powder and per serving each hide the one thing you are paying for. Here is the only unit that does not, and how we derive it.
Last updated: 18 May 2026.
The unit problem
A protein powder can be priced four ways, and three of them mislead. Price per tub ignores how much is in the tub. Price per kilo of powder looks fair but ignores how much of that powder is actually protein. Price per serving is the easiest to game, because the serving size is chosen by the seller. Only price per 100 g of protein measures the thing you are buying, which is protein, on a basis nobody can adjust for marketing.
Why per kilo of powder misleads
Two powders at an identical price per kilo can deliver very different amounts of protein. A concentrate, an isolate, a hydrolysate, a clear whey and a creamer-style blend all carry different protein shares per 100 g, and blends in particular carry added carbohydrate or fat that dilutes the protein further. Comparing them by powder weight ranks the most diluted product as competitively as the purest one. Comparing them by protein weight does not.
Why per serving misleads
The serving is a marketing lever. Shrink the scoop and the per-serving price falls, the per-serving protein falls with it, and the headline looks cheaper while nothing about the product changed. Any comparison anchored to a seller-defined serving inherits that distortion. A fixed, external basis removes it.
The price itself is not always comparable
Even a correct unit fails if the price feeding it is not a like-for-like price. Introductory and subscription prices, multi-buy bundles, free samples, multi-packs and tax-inclusive versus tax-exclusive figures are all genuine prices, but they are not the same kind of price. Treating them as interchangeable produces a ranking that rewards whichever listing happened to be on a promotion. Where the pricing of an offer cannot be resolved into a single clean one-off basis, we exclude it rather than rank a number we cannot stand behind.
How we compute it
The metric is derived once per product: a validated composition gives the protein content, a resolved clean price gives the cost, and one pure function turns the two into € per 100 g of protein. Composition and label transparency are weighed alongside it; price alone is never the ranking. Anything ambiguous on either side is held back, not averaged in. That is the difference between an editorial, validated ranking and a raw price feed.
How to use it
When you compare protein products yourself, convert everything to the same protein-weight basis before you decide, and discard any price that is a promotion or a bundle unless every option is on the same kind of deal. That is exactly what the engine does for you here. The full method is on the how we rank page, you can see it run on synthetic data on the demo, and the companion piece on label accuracy is why protein label claims are often wrong.