About
One number, honestly worked out
Protein Index ranks 38 UK protein powders by what 30g of actual protein costs you. Nothing else decides the order.
Why cost per 30g of protein
Tub prices are designed to be hard to compare. Pack sizes differ, scoop sizes differ, and the protein in each scoop differs by a long way. Two tubs at the same price can be miles apart on what you actually get. Cost per 30g of protein flattens all of that into one figure, because 30g is roughly what most people aim for in a serving. Across this index that figure runs from £0.54 to £3.27, a spread of 6.1x. Same powder category, same shaker, 6.1 times the cost. That gap is the whole reason this site exists.
Who is behind it
Protein Index is a small independent UK project, not a brand, not a retailer, and not owned by anyone who sells protein. Every price is recorded by hand or by an automated check against the retailer's own page, dated, and kept as history rather than overwritten, so a figure can always be traced back to when and where it was taken. Nutrition figures come from the manufacturer's own label. If something is wrong, tell us and it gets rechecked and relogged with a fresh date.
How it makes money
Some links to retailers earn a commission when you buy through them, and those links are labelled "Ad" right next to the link, never buried. That is the only way the site earns. No brand can pay to enter the index, to move up it, to have a rating changed, or to be left out of it. Commission has no bearing on the ranking, which is produced by one calculation applied identically to every product, including the ones that pay us nothing. If a cheap product that earns us nothing beats an expensive one that does, the cheap one wins, and it will say so.