Method
The Proof Score: five checks, 100 points
We do not taste-test vendors or average star ratings. The Proof Score asks one question five ways: could a stranger confirm this vendor's claims without buying anything? Every point maps to a source link on the vendor's page, and every source carries the date we read it. The current read is November 9, 2026, across 112 vendors.
| Check | Points | What earns them | Why it matters | Vendors passing now |
|---|---|---|---|---|
| Testing lab named | 20 | The vendor's own site names the third-party laboratory that issued its certificates of analysis. | An unnamed lab cannot be contacted, searched or cross-checked. | 46 of 112 |
| Lot lookup at the lab | 25 | From the vendor's site we could open at least one certificate on the laboratory's own domain — a hosted report or the lab's verification portal. | A PDF that only lives on the seller's server proves less than one the lab itself serves. | 19 of 112 |
| Street address published | 20 | A street address for the business appears on the vendor's site (contact page, terms, policies or footer). | A published address is the minimum needed to identify who is selling. | 39 of 112 |
| Independent review footprint | 20 | Live Trustpilot profile for the vendor's domain: 200+ reviews = 20, 50–199 = 14, 10–49 = 7, 1–9 = 3. No live profile, or not read = 0. | Review volume on a platform the vendor does not control shows a track record. Stars rate service, never the contents of a vial. | 70 of 112 |
| Dated public price | 15 | A price for a single-compound SKU (BPC-157 10mg where listed) visible without an account, recorded with the date we read it. | Prices you can see before checkout make like-for-like comparison possible. | 65 of 112 |
Bands
- Full paper trail: 85–100 points.
- Most of the paper trail: 60–84 points.
- Partial paper trail: 35–59 points.
- Thin paper trail: 0–34 points.
Ties
Vendors on the same score share a rank ("Shared #4"). Inside a tie we list names alphabetically, and the order means nothing.
Unknown is not the same as failed
Many sites block automated readers or hide certificates behind a login. When we cannot see something, the vendor gets zero points for that check and the page says unknown. We never fill a gap with a guess, and we never publish a negative claim we cannot link to.
What we read, exactly
- The vendor's homepage, contact, about, terms, privacy and certificate pages.
- Links from those pages to a lab's domain. A hosted report or a lab verification portal counts as a lot lookup.
- The vendor's public product data: list price for single-compound vials, before shipping or codes. We prefer BPC-157 10mg as the headline SKU because most vendors stock it.
- The Trustpilot profile for the vendor's own domain: review count and TrustScore on the read date.
Affiliation
USA Peptide Vendors is affiliated with Purgo Labs. Purgo is scored by the same code as everyone else, and its page and every comparison say so at the top. See our affiliations policy.
Questions
Does a high Proof Score mean a vendor's peptides are pure?
No. The score measures how much of a vendor's paper trail can be checked from outside. It is not a lab test of any vial and not a safety claim.
Why does an unknown score zero?
Points are only awarded for evidence we could open and cite. If we could not find or load something, it earns nothing, and the page says unknown rather than calling it a failure.
Does Purgo Labs get special treatment?
No. Purgo Labs is our affiliate and is scored by the same code as every other vendor. The affiliation is disclosed wherever Purgo appears.
Can a vendor get a score changed?
Yes, with a source. Send a link to the missing evidence and we re-read it; the new read date appears on the vendor's page.
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