How we test peptide suppliers
Our testing protocol is designed to replicate the experience of a standard retail buyer. No supplier is informed of the evaluation. No special arrangements, bulk pricing, or reviewer discounts are used. Every order goes through standard checkout using a standard shipping address.
Phase 1 — Procurement
Standard retail orders are placed during the evaluation window (typically 60 days). For each annual report, we order the five core compounds from each supplier where available: BPC-157, Semaglutide, NAD+, CJC-1295/Ipamorelin, and TB-500. Three suppliers in the 2026 evaluation did not carry all five compounds; they were scored only on available products.
Phase 2 — Blinding
Each sample is assigned a random 6-character alphanumeric identifier (e.g., “K7X2M9”). Original labels and packaging are removed. Samples are transferred to standardized vials. The testing laboratory receives no supplier information, compound names, or stated purity values.
Phase 3 — HPLC Analysis
Reversed-phase high-performance liquid chromatography (RP-HPLC) with UV detection at 220nm. Agilent 1260 Infinity II system. C18 column (4.6 x 250mm, 5µm). Each sample is run in triplicate with results averaged. Raw chromatograms are retained for all individual runs.
Phase 4 — Scoring
Six criteria are scored on a 0-10 scale:
| Criterion | Weight | What we measure |
|---|---|---|
| Purity Accuracy | 30% | How closely tested purity matches label claims across all compounds |
| COA Documentation | 20% | Whether batch-specific COAs are included, and if HPLC data is downloadable |
| Shipping Standards | 15% | Temperature-controlled packaging, insulated liners, cold packs, transit time |
| Catalog Breadth | 10% | Number of compounds available, research category coverage |
| Pricing & Value | 10% | Price transparency (no account required), per-unit value, bulk discounts |
| Research Support | 15% | Protocol guidance, dosing resources, AI tools, educational content |
Quality controls
- The testing facility is independent of any supplier evaluated.
- Samples are randomized in the order they are tested to control for any drift in instrument calibration.
- Each compound has a known reference standard run alongside test samples to validate the method.
- Results from each triplicate are reported individually before averaging; any single result more than 1.5% off the median is flagged for re-analysis.
Conflict of interest disclosure
Peptide Research Review maintains affiliate relationships with some of the suppliers it evaluates. Affiliate status has no influence on scoring — the testing lab does not know which samples come from affiliate suppliers. Rankings are determined solely by the rubric above.
Data availability
Full chromatograms for each tested sample are available on request. Email research@peptideresearchreviews.com with the sample identifier from the report.