Facts with a paper trail.

Manufacturer labels, specific variants

Only manufacturer product pages or their label text are used. Each record identifies its flavor and container where the source makes them clear. Whey concentrate includes blends whose manufacturer describes concentrate as a primary protein; isolate and plant are separate filters. These categories do not promise purity or certification.

Access before extraction

We fetch robots.txt first and review the manufacturer's public terms before requesting product pages. Requests identify as “AppBuilder-research (personal non-commercial)” and are separated by at least two seconds. We skip disallowed paths, terms that prohibit scraping or automated access, and unresolved access checks. No logins or captcha bypass. Access decisions and exclusions are recorded in research/ and data/missing.json.

Evidence you can inspect

Every published label value has a source ID and short verbatim quote matched against a cached manufacturer text during the build. Caches record the original URL, fetched-at time and user agent. The build works offline and fails on missing evidence. Research caches are not published in the site. We store no product prices; monetary fields are removed from cached product JSON, and monetary amounts are removed from extracted page text.

Visible gaps, no estimates

“not published” means the selected cached text did not unambiguously publish that value for the selected variant. Labels available only as images are not transcribed without verified text. Container weight and serving weight are never used to guess servings. Values from different flavors or sizes are never combined. Product selection is a research sample, not a ranking or recommendation.

Your calculation

Cost per 25 g = container price ÷ (servings × protein grams per serving ÷ 25). Enter a current price in any currency. We do not store or transmit your inputs. Zero is a valid amount; servings and protein must be positive finite numbers. Approximate label counts yield approximate results.

Disclosure and limits

No brand images or logos are used. Brand names identify products and remain their owners' trademarks. This site is independent. Affiliate disclosure: “Check price” slots are inactive, with no Associates ID; future affiliate links may earn a commission. This is not medical advice, and the calculator does not assess health suitability or protein quality. Confirm the current label before buying.

Research gaps

• Optimum Nutrition: General website terms could not be verified; no product fetch.
• Transparent Labs: Manufacturer terms prohibit scraping or automated access.
• Garden of Life: Manufacturer terms prohibit scraping or automated access.
• Vega: Manufacturer terms prohibit scraping or automated access.
• Ghost: Manufacturer terms prohibit scraping or automated access.
• Naked Nutrition: Manufacturer terms prohibit scraping or automated access.
• Momentous: Manufacturer terms prohibit scraping or automated access.
• NOW Foods: Terms could not be verified from public homepage; no product fetch.
• Kaged: Terms could not be verified from public homepage; no product fetch.
• Huel: Manufacturer terms prohibit scraping or automated access.
• Ritual: Manufacturer terms prohibit scraping or automated access.
• Thorne: Terms prohibit systematic retrieval to create a collection or database without written permission. Excluded at final policy review; preliminary product cache discarded.