Methodology
How we score peptide vendors.
Every vendor in our index gets the same five-category breakdown on a 0-10 scale. Scores are determined before any commercial relationship and revisited when vendors change pricing, ownership, or fulfillment.
The five categories
Purity & COA
Whether the vendor publishes per-batch HPLC certificates of analysis from a third-party lab, the mass-spec or HPLC purity claim, and whether COAs are accessible without contacting support. The single highest-weighted category in spirit, even though all five are scored equally — without verifiable purity, the rest is moot.
Price
List price compared against the median across the catalog, then adjusted for active discount codes, shipping cost, and free-shipping thresholds. Bulk discounts and bundle pricing factor in. We score the real out-the-door cost, not the headline price.
Shipping
Time-in-transit observed across multiple test orders, packaging quality (cold-chain where required), tracking accuracy, and international availability. Domestic-only vendors are not penalized as long as in-country shipping is fast and reliable.
Service
Response time to support tickets, willingness to replace damaged or short-shipped orders, return/refund policy clarity, and overall communication quality. Tested via real questions about COAs, shipping, and product specs.
Selection
Catalog depth across the categories that matter — healing peptides, GLP-1s, longevity compounds, GHRPs, cognitive peptides, and supplies (bac water, syringes). Vendors that cover the whole stack score higher than single-category specialists.
What we don't do
We do not sell peptides. We do not run a vendor's checkout. We do not accept payment to rank a vendor higher. Affiliate relationships exist with some of the suppliers we review — that is how the site sustains itself — but those relationships are entered into after a vendor enters our index, and ranking is never adjusted in exchange for revenue share.
We also don't make medical claims. Peptides indexed on this site are research chemicals. We describe what each compound is in biochemical terms; we do not tell you what it does to your body because that is not something this site is qualified to answer.
When scores change
Scores are reviewed when a vendor changes ownership, sources, or pricing structure; when we observe consistent shipping or service regressions; or when a new third-party COA flags a purity issue. We add a revised-on date to vendor pages whenever scores move.