What a vendor comparison actually needs
The research-peptide market is opaque by default: dozens of vendors sell the same catalog compounds at prices that differ by a factor of three or more, and the listing price tells you almost nothing on its own. A fair comparison needs three normalized inputs, not a screenshot of a checkout page.
Normalize the price first
Vendors quote vials — 2 mg, 5 mg, 10 mg — so the only comparable unit is price per milligram. A "cheaper" 5 mg vial can cost more per mg than a larger one from the same vendor, and bundle discounts routinely distort the top-line number. Shipping minimums and regional pricing push the real figure further away from the sticker. Any price table that is not per-mg normalized is a marketing document, not a comparison.
Date the purity claim
Nearly every vendor posts purity percentages, usually 98–99%+. The claims that matter carry a certificate of analysis with a test date, a lot number that matches the vial being shipped, and a named third-party lab. Undated COAs, in-house-only testing, and lot numbers that never line up with the shipped product are the three most common failure patterns. A purity figure without a date is a snapshot of nothing.
Score trust separately from price
Cheap and trustworthy are different axes. Useful trust signals are consistency — does batch three test like batch one — plus how a vendor behaves when a customer reports a problem, and whether the operation publishes its testing at all without being chased. Blind-test programs, where samples are ordered and tested without the vendor knowing, remove the self-reporting bias that plagues vendor-owned "lab results" pages.
Where the comparisons live
Per-mg price normalization, dated purity records, blind-test trust scores and a public vendor-warnings list for the vendors we track are maintained at Peptide Compare. Every figure there is sourced and dated, and the method behind the rankings is published in the open.
For informational and comparison purposes only — not medical advice. Peptide Compare does not sell or manufacture peptides.