Methodology

The share of a product’s calories that come from protein.

protein grams × 4 ÷ calories

Protein carries 4 calories per gram, so a 120-calorie scoop with 24 g of protein is 80% protein. Labels round calories to the nearest 5 or 10 and protein to the nearest gram, which can push a very lean product past 100%: 18 g of protein is 72 calories on a label that says 70. Nothing is more than 100% protein, so we cap the measure there and show the label math on the product page.

Concentration tells you how much protein you get for your calorie budget. It says nothing about protein quality: collagen scores high here but lacks the essential amino acid tryptophan, so it isn’t a complete protein. Product pages note this where it applies.

For now, taste is the product’s average customer star rating at a major retailer (Amazon first, then Walmart, Target or the brand’s own store). A raw average rewards products with only a few reviews, so each rating is blended with 100 imaginary ratings at the average across all products:

(stars × ratings + average × 100) ÷ (ratings + 100)

Star ratings measure more than taste (texture, mixability, shipping damage) and usually pool every flavor of a product. That is why this is a stand-in. The plan is to replace it with blind, side-by-side tastings, where people pick the better of two samples and products earn an Elo-style score, the way chatbot arenas rank language models.

Whole foods have no taste score.

What one gram of protein costs at the everyday price of a common package.

package price ÷ servings per package ÷ protein grams per serving

The everyday price is what people typically pay: Amazon’s “typical price” when it shows one, otherwise the retailer’s non-sale shelf price. We never use a temporary deal, a subscribe-and-save price, or a struck-through “list price”, which is often higher than anyone pays. We price a package size most people buy. Bigger tubs and club-store packs are usually cheaper per gram; we note the package on every product page. Whole foods use the Bureau of Labor Statistics national average retail price where BLS tracks the item, and a Walmart store-brand price where it doesn’t.

Each category gets a grade from A to E on every measure. We take the category’s median product and rank it against all products in every category: A means it beats at least 80% of them, B at least 60%, and so on down to E for the bottom fifth. For cost, beating means being cheaper.

Grades compare across categories on purpose. A D for protein bars on protein per calorie means the typical bar has less protein per calorie than most protein products overall, not that it’s a bad bar.