Overall findings
Most lab-test failures
Vendors with the most tested samples showing at least one problem.
Peptide vendor rankings
Compare peptide vendors.
Start with the evidence.
Explore international vendors and domestic resellers, compare lab-test problems, or go straight to the compound you’re researching.
104,157 published COA report entries 132 ranked vendors
Data refreshed Report dates are shown with each test.
Choose a ranking
International vendors or domestic resellers?
Start with the type of seller. Both rankings count unique independent lab reports, so more reports means more evidence to review.
30 reviewed vendors
International vendors
Compare manufacturers, exporters and other international sellers by their independent lab reports.
7,164Unique lab reports 12Observed in 30 days View full ranking →102 reviewed vendors
Domestic resellers
Compare U.S.-based resellers. The seller is domestic; the product may still come from an overseas supplier.
15,803Unique lab reports 38Observed in 30 days View full ranking →What is a domestic reseller?
A reseller buys from another supplier and sells under its own storefront or brand. Here, domestic means U.S.-based. Local shipping does not mean the product was made in the U.S. or tested after resale. Check the report for the actual batch.
Follow the evidence
Where the tests went wrong.
Recorded failures alongside the number of applicable tests. Choose a seller group to see the results behind each count.
Contamination findings
Failed endotoxin tests
Compare repeated failures in tests for bacterial endotoxins.
Below 97% purity
Low purity results
Vendors with the most measured purity results below 97%.
At least 10% short
Underfilled samples
See where tests found less compound than the stated amount.
Identity findings
Compound not found
Vendors with the most results that did not find the labeled compound.
What these counts include
All available results in the lab-findings comparisons. Each category counts only applicable tests; missing measurements do not count as passes. One sample can appear in several categories, but counts once in the overall total. These are counts of tested samples, not failure rates for everything a vendor sells.
International vendors: Recorded lab dates 2022-06-24 to 2026-09-08. 5 measured results have no usable date.
Domestic resellers: Recorded lab dates 2020-01-31 to 2026-09-11. 23 measured results have no usable date.
Choose your compound
Compare lab results
by compound.
Explore measured results, compare vendors and open their lab reports. These figures cover the same reviewed seller groups as the findings above.
GLP-1 and related compounds
RetatrutideLab results by vendor↗ International vendors1,645 measured results69.6–100% purity in 1,588 results Domestic resellers1,885 measured results40.86–100% purity in 1,741 results TirzepatideLab results by vendor↗ International vendors1,213 measured results85.9–100% purity in 1,188 results Domestic resellers1,336 measured results91.22–100% purity in 1,235 resultsGrowth hormone and related compounds
HGHLab results by vendor↗ International vendors78 measured results90.45–99.9% purity in 75 results Domestic resellers9 measured results96.14–99.84% purity in 9 results TesamorelinLab results by vendor↗ International vendors371 measured results12.7–100% purity in 353 results Domestic resellers543 measured results48.94–99.99% purity in 486 resultsRanges include measured purity above 0%. “Compound not found” is counted separately. The report library has broader coverage; vendor rankings apply their own minimum test counts.
Beyond the lab
What was it like to order?
Buyer reviews cover delivery, communication and service. Each keeps its date and source.