Monthly report

State of Peptide Vendors: October 2026

Our vendor ratings for October 2026, computed from the audit data behind every score: who was reviewed, how the scores moved, and what the certificates show. Research use only; nothing here is a health or dosing claim.

Vendors at month end
92

Vendors at month end

Median score
6.52

Median score

Summary

At the end of October 2026, reconstructed from score histories, 92 vendors were listed with a median overall score of 6.52 of 10. In October 2026: 41 vendors published for the first time, 437 score moves of 0.05 points or more were logged across 83 vendors (243 up, 194 down), 1 vendor removed, 4 laboratories found not to be established as independent. The largest rise was Felix Chemical Supply (2.73 to 7.53). The largest fall was BioInfinity (8.48 to 3.70).

Affiliate status never affects scores. Whether a vendor pays us a commission, declined to, or was never asked carries no weight in the formula. How we keep it that way.

Headline numbers

Reconstructed for October 31, 2026 from each listed vendor’s dated score history. Vendors removed since then are not included (Soma Chems): their records were removed with them. The testing gate, lab scores and certificate counts are not recorded by date, so they are not reconstructed for a past month.

Vendors listed at month end
92
Median overall score
6.52
Out of 10

Vendors by tier

Excellent0 (0%)Strong31 (34%)Fair33 (36%)Weak9 (10%)Poor19 (21%)
Listed vendors by tier on October 31, 2026, reconstructed from score histories.

Movers

Net change over the month for each vendor whose score moved by 0.05 points or more, from the dated audit history. Each name links to that vendor’s full score history. 437 moves of that size were logged (243 up, 194 down) across 768 audit entries.

Biggest rises

  1. Felix Chemical Supply2.73 → 7.53 (+4.80)net of 5 entries
  2. Paramount Peptides3.29 → 7.13 (+3.84)net of 13 entries
  3. Core Peptides3.11 → 6.54 (+3.43)net of 9 entries
  4. Cernum Biosciences2.05 → 5.24 (+3.19)net of 10 entries
  5. Direct Peptides4.87 → 7.36 (+2.49)net of 7 entries
  6. Biotech Peptides4.11 → 5.79 (+1.68)net of 7 entries
  7. Peptix USA6.59 → 8.09 (+1.50)net of 8 entries
  8. Transition Biotech6.50 → 7.98 (+1.48)net of 6 entries

Biggest falls

  1. BioInfinity8.48 → 3.70 (-4.78)net of 10 entries
  2. Nextday Peptides7.28 → 3.20 (-4.08)net of 16 entries
  3. Drexa Labs7.11 → 3.33 (-3.78)net of 5 entries
  4. PSPeptides6.97 → 3.95 (-3.02)net of 11 entries
  5. Peptide Pros6.54 → 3.56 (-2.98)net of 10 entries
  6. GenX Bio6.19 → 3.68 (-2.51)net of 9 entries
  7. Spartan Peptides5.26 → 3.43 (-1.83)net of 8 entries
  8. Limitless Biotech8.55 → 6.85 (-1.70)net of 6 entries

Vendors added and removed

First published (41)

Removed (1)

  • Ion Peptide, October 26, 2026: removed at the editor's discretion; not a finding about its products, certificates or conduct.

Laboratories and certificates

33 laboratory gradings were last checked this month. Our laboratory records carry the date of a finding that a laboratory’s independence was not established, but not the date a laboratory was first added or its earlier tier, so other additions and tier changes are not listed here. Every tier is on the laboratory directory.

Of the certificates on file today, 153 carry a laboratory test date in October 2026. Their median printed purity is 99.78%, 92% were confirmed at the issuing laboratory, and 50% include an endotoxin or sterility test.

Methodology

Every number on this page is generated from the same audit data as the rankings when the site is built, with no hand-entered figures. Scores, tiers and the testing gate follow our published methodology. Certificates on file are those from laboratories whose independence we could establish; a certificate counts as confirmed when its verification key was checked at the issuing laboratory. Purity is the figure printed on the certificate. Movers are net changes over the month from the dated history on score changes. A past month reports its dated changes; its month-end state is shown only where the data records it.

Cite this report

Peptide Source Review. "State of Peptide Vendors: October 2026." Published for October 2026. https://peptidesourcereview.com/state-of-peptide-vendors/2026-10

Data: https://peptidesourcereview.com/state-of-peptide-vendors/2026-10.csv, licensed CC BY 4.0. Please credit Peptide Source Review and link this page.

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