How we score peptide vendors
We don’t sell peptides, we grade the vendors who do. Every grade is built the same way: eight weighted criteria, a binding integrity gate, and a confidence label, all from dated evidence you can check. You could follow these steps and reach the same result.
The eight criteria
Each vendor is scored 0–100 on eight criteria. The weights sum to 100% and reflect how much each factor tells you about a vendor. Lab testing and purity carry the most weight on purpose, they are the hardest things to misrepresent.
Has an independent lab tested the product, and are the published Certificates of Analysis current and tied to the named lab and lot?
The purity result and contaminant findings from independent testing.
How openly the vendor discloses sourcing, testing, identity, and policies.
Track record with buyers, and how the vendor handles support and problems.
Site quality and operational signals of a legitimate, functioning business.
Price relative to what you actually get, including independently verified purity.
Order accuracy, packaging quality, and delivery reliability.
Range of payment methods and the trust signals at checkout.
From 0–100 to a letter
We multiply each criterion by its weight, add them into a single 0–100 composite, then map it to a letter. We use +/− steps within each tier (e.g. A−, B+).
Vendors are ranked by composite score, highest first. Ties break toward the higher confidence label. Sponsored placements never enter the ranking.
The integrity gate
Some findings matter more than any weighted average. The gate is a binding cap that sits on top of the composite, because the whole point of a grade is trust.
No independent COA → capped at D+
A vendor with no independent third‑party Certificate of Analysis cannot score above the D band (max 69/100), no matter how polished the rest of the operation looks.
Fabricated evidence → capped at F
A vendor caught publishing fabricated or reused COAs, or fake reviews, is capped at F and flagged with the specific, dated observation behind it.
Confidence labels
A grade is only as good as the evidence behind it. Read the confidence label as carefully as the letter, a high grade at Limited confidence means “looks good so far, but we don’t have much to go on yet.”
At least one independent test or per‑lot COA in the past 12 months, and 20+ independent community data points.
An independent COA is present but sparse, or there are 5–19 community data points.
Vendor‑supplied data only, fewer than 5 data points, or any criterion left unscored, provisional.
Money never changes a grade
We earn from affiliate links and clearly‑labelled sponsored placements. The same rubric applies to paying and non‑paying vendors alike; sponsored slots stay out of the merit ranking; affiliate links are disclosed. If a vendor pays us and earns a poor grade, it earns a poor grade.
Read our full disclosure →How to read a scorecard
- 1Read the grade and confidence together
A B+ at High confidence is a very different thing from a B+ at Limited confidence.
- 2Check the integrity gate first
If a vendor is capped or flagged, the detail explains exactly why.
- 3Look at the top two criteria
Independent testing and measured purity carry the most weight and the most reliable evidence.
- 4Note the measured-vs-editorial tags
Measured scores are facts with linked evidence; editorial scores are our reasoned, labelled opinion.
- 5Read the dates
Check when the evidence was last refreshed against our re-review cadence.
Evidence & re‑review
How we source evidence
- Independent test‑buys, we buy as an ordinary customer and send to an independent lab; the vendor doesn’t know which order is ours.
- Vendor‑published COAs, verified against the named lab and stated lot, not taken at face value.
- Community sampling, named sources, a stated date range, a minimum data‑point count, outliers and astroturf excluded.
How often we re‑review
- PricingQuarterly
- COA & purityPer batch · 6 mo
- ReputationEvery 6 months
- Full re‑gradeAnnually
Methodology version v1.0, published 29 June 2026. Material changes are versioned and dated here and trigger a full re‑grade. Every vendor gets a free right of reply.