How peptide prices are read and ranked

1. The shops are read

A gatherer on the shared server reads each shop's product pages every few hours (or the feed a claimed shop hands over): name, quantity, price and currency, the container where the title or the description states it, pack size, shipping where the shop states it, batch and test report where the page prints them. Every price tag shows when its price was read. A shop or a product the gatherer did not read is not on the floor; nothing is estimated in between runs.

2. The tag: price per milligram

The listed price divided by the stated quantity. A pack of vials is priced as the pack, and the tag says so. A listing with no stated quantity carries no per-milligram tag; it still appears in the rankings, marked. Raw or bulk powder is not a ready product and is kept off the shelf, listed separately for completeness.

3. The delivered price per injected milligram

Set your dose and how often you inject. The tag then counts what the format makes you buy, at one reference price per country, the same for every product: water for a lyophilised vial, insulin syringes or pen needles for the injections you can actually give, swabs, and the shop's own stated shipping. It divides by the milligrams that fall inside the days the product stays usable, so a vial whose contents outlast its usable window is not credited with doses you would throw away. Containers known to the engine: Dual-chamber pen, Lyophilised vial, Lyoprester cartridge + EZnject kit, Pre-mixed liquid, Raw / bulk powder (not a ready product).

4. The three rankings

Best price orders by the product-only price per milligram. Best value orders by the delivered price per injected milligram. Best overall is a weighted score, each part between 0 and 1 against the best on the page: value 0.3, days usable at your schedule 0.2, the container (handling steps, septum exposures, closure, drying, shelf life) 0.4, quantity 0.1. Every product's score opens to show every line.

5. What is not counted, and says so

Shipping a shop does not state. A pen device for a cartridge refill. A quantity a shop does not state. A discount a shop promises to visitors who come through the sister site counts, and the tag says the price is yours only through there.

6. The badge beside a shop

Unverified, Claimed, Documents on file, CTP Verified: what the sister site itself has checked about a shop, never what the shop declares about itself. Role labels (manufacturer, lyophiliser, liquid filler, reseller) are the shop's own declaration once it has claimed its listing, and presumed before. The levels, the evidence each needs and the published proof are at Compare The Peptide. Shops are never charged for a badge, a listing, a ranking or a click.

7. Corrections

A wrong price, a wrong quantity, a missing shop: write to hello@comparethepeptide.org. A shop can claim its listing and hand over a feed, after which its own data stands in for what the gatherer read.

The record behind every shelf (what the peptide is, what has been studied, its sources, PubMed first: pubmed.ncbi.nlm.nih.gov) is kept once, on Compare The Peptide; a shelf here links to it rather than repeating it.