We grade the vendors, so you don’t gamble
Buying research peptides means trusting a website with your money and your work. Most of those websites publish no independent proof at all. We exist to change the incentives: grade every vendor in public, on evidence, with a methodology anyone can check.
What we do
Checkthevendor is an independent grading and comparison site for peptide vendors. We do not sell peptides, and we never will. Every vendor gets the same treatment: a 0 to 100 composite score across eight weighted criteria, a binding integrity gate, a confidence label, and a public scorecard with the evidence behind it.
What we believe
Evidence beats vibes
A polished website proves nothing. Independent lab results, verifiable COAs, and dated observations are the only inputs that move a grade. The hardest things to fake carry the most weight.
Grades are not for sale
We earn from affiliate links and clearly labelled sponsored placements, and none of it touches a score. A paying vendor with bad evidence gets a bad grade. Read the full disclosure.
Grades must stay alive
A rating from last year is a rumor. Scores carry review dates, re-review cadences, and a public change log, and every vendor gets a free right of reply.
How a grade is built
- 1Collect evidence
Vendor-published COAs verified against the named lab, independent test purchases where available, and community data points with named sources and date ranges.
- 2Score eight criteria
Lab testing, measured purity, transparency, reputation, pricing, shipping, payment trust, and operational trust. Weights are public and sum to 100.
- 3Apply the integrity gate
No independent COA caps the grade at D+. Fabricated evidence caps it at F. No average can buy its way past the gate.
- 4Label the confidence
High, Medium, or Limited, so you always know how much evidence sits behind a score.
- 5Publish and re-review
Every scorecard shows its evidence, its dates, and when we will look again.
The full methodology, including every weight and threshold, lives on How we score.
Who is behind this
Checkthevendor is run by a small independent editorial team. We keep our grading identity collective on purpose: grades follow the published methodology, not any one person’s taste, and every published grade is accountable to our editorial policy, corrections process, and right of reply. If we get something wrong, tell us and we will fix it in public.
See the grades for yourself
Every score, every weight, every date, in public.