Independent testing labs
Third-party testing is how a peptide's purity and identity get verified independently of the seller. Below are the labs and aggregators most referenced in the community — an informational directory ordered by how widely each is referenced, not a quality ranking or an endorsement. We don't test peptides ourselves; any grade on this site is attributed to its source.
Testing labs
Labs that run the actual assays — HPLC purity, mass-spectrometry identity, sterility.
Janoshik Analytical
janoshik.com ↗The most widely-referenced independent lab in the peptide community. Reports HPLC purity and mass-spectrometry identity (with sterility/endotoxin on request) and lets buyers verify a report by its reference number.
MZ Biolabs
A US-based analytical laboratory offering peptide identity and purity testing.
Colmaric Analyticals
An independent laboratory providing peptide and certificate-of-analysis testing services.
Aggregators & raters
Services that compile or classify test results across vendors.
Finnrick
finnrick.com ↗Aggregates independent test results into per-vendor letter grades (A–E). It is the source we attribute the vendor grades on this site to.
PeptideBenchmark
A transparency classifier that rates how verifiable a vendor's published COAs are — e.g. a report hosted on the lab's own domain versus a vendor-supplied PDF or image.
How to read a test report
Purity, net peptide content, and identity are three different numbers — see our explainer on how to read an independent peptide test report.