Independent Peptide Source Reviews of 100 US Vendors
Every vendor scored on the same published formula: lab credibility, shipping integrity, pricing, operating history, transparency. Weighted, capped, never moved by sponsorship.
- Vendors audited
- 100
Vendors audited
- COAs read and checked
- 1,674
COAs read and checked
- Analytical labs
- 32
Analytical labs
- Peptides tracked
- 71
Peptides tracked
Last audit update: November 6, 2026 · same published formula for every vendor
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The full directory
All 100 vendors, ranked
Search, sort, and expand any row for the sub-score breakdown. Click through for the full audit: labs used, COA coverage, shipping terms, price per milligram.
How a score is built
The full method- Step 1
We read the certificate
Every certificate on a vendor's page is opened and read: the laboratory that issued it, the batch, the tests run and the purity it reports.
- Step 2
We check it with the lab
Where the laboratory offers a lookup, we enter the key printed on the report and record whether the laboratory finds it. Each laboratory is graded on six published checks.
- Step 3
One formula for every vendor
Lab credibility carries 55% of the score, then shipping 20%, pricing 15%, operating history 5% and transparency 5%. Affiliate status never moves a score.
More reader deals
Affiliate links: we may earn a commission if you buy. It never changes a score or rank.
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Certificates from 32 named analytical labs
Why trust this directory
Built like a lab audit, not a listicle
We read the COAs ourselves
Every certificate we count as verified has been read, and confirmed at the issuing laboratory where it offers a lookup: batch numbers, purity, endotoxin panels. A vendor saying “third-party tested” means nothing until the paper holds up.
Published formula
Lab 55% · shipping 20% · pricing 15% · history 5% · transparency 5%. The same math for all 100 vendors.
No pay-to-rank
Sponsorship can move visibility, never a score. Vendors whose testing we cannot verify are held under a ceiling of 6.0, raised by at most 2.5 points for long operating history, strong shipping and large review counts.
Testing gate
Vendors whose testing can’t be independently verified hit a score cap. The gate is visible on every review, with the reason spelled out. It records that testing could not be verified, not a finding of a quality or safety problem.
The formula
One score. Five ingredients.
COA depth, lab named, independently verified
speed, tracking, reship policy
price per mg vs the market
years live, continuity
ownership, contact, terms
Then the gate: if a vendor’s third-party testing can’t be independently verified, the final score is capped at 6.0 plus limited allowances (8.5 at most) for operating history, shipping and reviews. Pricing never lifts it. Trust is earned on paper.
Browse by peptide
Find the best vendors for your compound
Every compound ranked from the same audited vendor pool. Jump straight to a ranking, or read the primer first.
GLP-1 family & GH fragments
The most-searched category: incretin-receptor agonists, amylin analogs and related compounds.
Peptide fragments & copper peptides
BPC-157, thymosin beta-4 fragments, copper tripeptides and KPV.
Growth hormone secretagogues
GHRH analogs, ghrelin-receptor agonists and IGF-1 analogs.
Neuropeptide analogs, cofactors & other
Neuropeptide analogs, mitochondrial peptides, NAD+ and melanocortin peptides.
Bioregulators
Short peptide bioregulators from the Russian Khavinson research programme.
Freshly audited
Recently updated
100 vendors audited and 1674 COAs read and checked, last updated November 6, 2026. The most recently re-scored vendors:
From the same team
Gym Product Review
We built a second directory that rates gym supplements the way we rate peptide vendors: a published formula, cost per gram calculated from the label, and no pay-to-rank. Protein, pre-workouts, energy drinks, creatine, electrolytes and more.
A separate site for consumer supplements. Everything on Peptide Source Review remains research use only.