Transparency Report
The State of EU Peptide Testing 2026
Most research-peptide vendors publish a certificate when the number flatters them and stay quiet when it doesn't. We took the opposite position: we publish every Janoshik report we commission — including the ones we'd rather not. This page aggregates that record so far. It is a living document, refreshed each testing cycle.
Data as of 2026-06-10 · 16 independent Janoshik reports · 16 compounds
Why publish the unflattering results
A certificate of analysis is only worth what the testing behind it is worth — and worth far less if a vendor only shows you the reports that look good. The value of a third-party report comes precisely from the fact that the vendor didn't get to choose the number. When a supplier curates which lots they publish, they quietly convert independent testing back into a marketing claim.
So our rule is simple. Every Janoshik Analytical report we pay for goes on the public COA wall, verbatim, whatever it says — and you can open the original on Janoshik's own verification portal, not a PDF we re-typed. Two of our published purity lots came back below 99%. They are on this page by name. That is the whole point.
The aggregate, as published
Every figure below is computed directly from our published Janoshik reports — no external survey, no competitor numbers, no estimates. Content-quantification assays (blends and bacteriostatic water, which have no single purity percentage) are counted separately so they never inflate the purity statistics.
Testing window: 2026-03-31 → 2026-05-28
The two lots we'd rather not show you
Headline purity numbers are easy to average up if you hide the tail. Here is ours, unhidden. Both lots cleared our published ≥98% HPLC floor; neither reached the ≥99% most of our catalogue runs at.
We left these reports live and on the wall. A vendor that has never published a sub-99% result either tests far less than it implies or shows you only the good ones.
Methodology, in plain terms
Three different instruments answer three different questions, and conflating them is a common way to overstate a COA.
HPLC — how pure is it?
Reversed-phase high-performance liquid chromatography separates a peptide from its related impurities; purity is reported by area normalisation — every detectable peak integrated, the main peak expressed as a percentage of the total. This is the number researchers usually mean by "purity."
MS — is it the right molecule?
Mass spectrometry confirms identity by measuring the molecule's mass-to-charge ratio against its known molecular weight. High purity of the wrong compound is worthless; MS is what rules that out.
ICP-MS — is it contaminated?
Inductively coupled plasma mass spectrometry detects trace elements — arsenic, cadmium, lead, mercury — down to parts-per-billion. It is a separate panel from purity, and we run it as standard on copper peptides such as GHK-Cu.
Content quantification answers a fourth question — how many milligrams are actually in the vial — which is why we report it separately and never fold it into a purity average. A blend with three actives has no single purity figure at all.
About the lab, stated precisely
Our reports are issued by Janoshik Analytical, an independent third-party testing laboratory in the Czech Republic widely used across the research-compound community. We are a reseller: CertaPeptides does not run HPLC, MS, or ICP-MS in-house, we do not manufacture or formulate these compounds, and we hold no laboratory certification of our own — the trust comes from the independent lab, not from us. What we control is which lots we send for independent testing, and the decision to publish all of it.
What to demand from any EU supplier
Whether or not you buy from us, these are the questions that separate a real testing programme from a marketing one. Use them on every vendor.
A report you can open at the lab, not a PDF they typed
A verification link to the testing lab's own portal cannot be edited after the fact. A re-typed or screenshotted COA can. Insist on the former.
The lot number on your vial, matched to a report
A report for "some batch" proves nothing about your batch. Ask how a code printed on your vial maps to a specific published report.
At least one result they'd rather not show
A wall of flawless certificates is a red flag, not a green one. Real testing produces the occasional disappointing number. Ask to see theirs.
Honest scope — purity is not identity is not heavy metals
A purity percentage doesn't tell you the molecule is correct or the metals are clean. A supplier who blurs the three is overstating their COA.
Questions researchers ask
Is this an EU-wide market survey?
No, and we won't dress it up as one. It is an aggregate of our own published Janoshik reports — first-hand data from lots we tested, not a survey of other suppliers. We frame it as a European reference because the underlying transparency standard travels: any EU buyer can apply the same checklist to any vendor.
Why do some entries have no purity percentage?
Blends with multiple actives and bacteriostatic water are sent for content quantification — how many milligrams of each component are present — not single-compound purity. There is no honest way to express a three-active blend as one purity number, so we report and count those separately.
Do you test every batch?
No. Independent testing runs on selected lots on a rolling cycle, and supplier batch specifications cover every product line in between. We don't claim per-vial third-party testing, because we don't do it — anyone who claims it for an entire catalogue is overstating.
What happens if a lot fails?
If a published lot returns below our ≥98% HPLC floor, we replace it or make it right on request for any unit from that lot, and the report stays public either way. We don't quietly delete inconvenient results.
See the underlying reports
This page is the summary. The evidence is the wall: every report it aggregates, openable at Janoshik's portal.
All CertaPeptides products are supplied strictly for laboratory research purposes only. Nothing here is a medical claim, and none of these compounds are for human or veterinary use.