About PeptidesFinder

Editorial work on this site is published under the byline J. Mercer. That is a pen name, and saying so here is deliberate. This site publishes findings that suppliers do not always like — that a store’s prices moved, that a testing claim has no certificate behind it, that a link no longer resolves — and the byline is a pseudonym for that reason. It is disclosed rather than dressed up: there is no invented biography behind it, and you will not find a fabricated CV, institution or headshot on this page.

What the role covers is verifiable, because you can check the output against the vendors’ own storefronts:

• maintaining the price index — which stores are in it, which retrieval method each one needs, and which listings get retired;
• reviewing certificates of analysis and third-party testing claims before a testing badge is allowed onto a listing;
• deciding what is published: which submitted vendors are approved into the directory, which prices are promoted from pending to live, and which reviews are approved.

Accountability runs through one address rather than a name: admin@peptidesfinder.com. Corrections sent there are acted on, and a correction that stands is applied to the data, not argued with.

There are two revenue sources, and both are disclosed on the pages they affect.

• Affiliate links. Some outbound links to vendors are referral links that earn a commission when someone buys, at no extra cost to the buyer. Every one of them is marked rel="sponsored" in the page source, which is the same signal search engines are told to read them by.
• Paid vendor listings. Suppliers can pay for a Pro listing or a Featured slot. What that buys is placement and profile features — a highlighted card, a position nearer the top of the directory, a richer profile.

What paying does not buy. It does not buy a rating, a testing badge, a review, or a better position in the price index. Ratings come from an editorial score and from approved user reviews; testing badges appear only when the underlying record exists. The price index sorts on price per milligram — a paid vendor with an expensive listing sits at the bottom of that table like anyone else. Where paid placement does move a vendor up the directory, the card is labelled Featured so you can see it happening, and the Featured slot itself is only offered to vendors already rated 4.5 stars or better.

Wholesale suppliers are never linked off-site and are tagged as a separate market, so a bulk kit price is never ranked against single retail vials.

1. Read from the vendor’s own public storefront. Prices come from the store pages anyone can load — a product feed, a catalogue page, the listing itself. Suppliers whose robots.txt asks automated clients to stay out are marked as such and are not read at all.
2. Read the whole catalogue, not a sample. A partial read publishes a “cheapest price” that is only the cheapest of the part that was read, which is worse than publishing nothing.
3. Normalise to price per milligram. The sticker price stays in the vendor’s own currency; the comparison figure is converted to USD and divided by the total milligrams in the pack, so multi-vial kits and mg/mL concentrations are multiplied out rather than misread.
4. Check it before it goes live. A listing is only shown publicly when its link still resolves, its price passes an automated outlier check, and the vendor is active. A price that fails either check is withheld rather than published with a caveat. Each row carries the date it was last confirmed against the vendor’s page, and that date is shown to you.
5. A failed fetch is not evidence of anything. If a store stops responding, that is recorded as a store we could not read — not as a store that closed. This site does not declare a business dead because a request timed out.

Prices change constantly, and a store can change one between the last check and your click. The date on each row is there so you can judge for yourself; the vendor’s own page is always the final word.