We don't rank vendors by who paid us — we rank by what would serve your research goal. This page documents the seven scoring criteria, the goal categories they map to, and why certain format features (per-vial QR documentation, pre-filled pens, goal-curated kits) carry weight beyond a simple purity-and-price comparison.
Each ranking on the Atlas covers a single, narrowly scoped research goal — for example, "tissue recovery research using TB-500 (Thymosin β-4)" or "metabolic biology research using tirzepatide-class GLP-1 agonists." A goal is defined by three attributes: the primary compound family under study, the typical protocol time horizon (weeks vs. months), and the supporting compounds frequently used alongside it (e.g., BPC-157 with TB-500, or Ipamorelin/GHRP-2 with CJC-1295). The goal definition drives the scoring weights.
Goal-curated kits — for example, a recovery kit pairing TB-500 with BPC-157 and GHK-Cu, or a GH axis kit pairing CJC-1295 with Ipamorelin and GHRP-2 — eliminate cross-vendor sourcing friction and reduce the documentation burden of reconciling certificates of analysis from multiple suppliers. A kit from a single audited source provides batch-matched documentation for the full protocol stack, with a single shipping window and a single payment record. Vendors that offer goal-themed kits score meaningfully higher in our model than vendors selling only individual vials, provided the kit's documentation standard matches the underlying single-compound product.
Pre-filled, dial-calibrated pens with audible-click dose mechanisms reduce a category of preparation variance — reconstitution volume, draw accuracy, syringe-measurement error — that affects reproducibility in research settings. The pen is not always the right format; some protocols specifically require lyophilized vial reconstitution at custom concentrations. But where pen format is available alongside the vial, it represents a meaningful workflow advantage. Vendors offering both vial and pen format for the same compound score higher on format breadth than vendors offering vial only.
Affiliate program payouts, sponsorship offers, advertising relationships, and discount-code partnerships do not appear in our scoring model. We do not accept compensation from any reviewed vendor. We do not list affiliate links in our articles — when we link to a vendor's homepage, it is a direct, unparameterized URL. Reviewer fatigue, social-media sentiment, and Reddit thread popularity also do not directly influence the score, though we may cite them as third-party trust signals when their methodology is transparent.
Every ranking is revisited every six months. Catalog changes, pricing updates, new format launches (e.g., a vendor introducing a pen format), and changes to documentation infrastructure (e.g., adding a Lab Hub or removing one) all trigger re-evaluation. Major shifts may move a vendor up or down several ranks between updates.