There’s a particular kind of frustration in finding a supplier that describes its testing beautifully and then asks you to create an account before you can read a single document. The description might be entirely accurate. The panel might be the widest in the market. And you’re still being asked to hand over your details in exchange for evidence you’d normally expect to see before deciding anything, which changes the order of operations in a way that’s worth noticing.
Swiss Chems and Certified-Pep both publish detailed statements about how their material gets tested, and they make those documents available on different terms. I set five questions before opening either site, asked them in the same order of both companies, and awarded nothing for tone or presentation. I have no stake in either business.
Everything below is what each site publicly states on the pages I could reach on 2026-09-08. Where a company answers a question I quote it, and where it doesn’t I record the gap and date it, which is a narrower claim than it might look at first reading.
Key takeaways
- Sort suppliers on five documentary questions rather than on presentation: who synthesizes, which laboratory tests, how wide the panel runs, whether a lot-specific certificate is readable before payment, and whether blends state milligrams per component.
- Swiss Chems states that “every compound we supply undergoes independent third-party HPLC testing and is verified to a purity standard of 99% or higher”, names its principal third-party laboratory in the FAQ, and publishes fifty downloadable reports openly.
- Certified-Pep names “Vanguard Laboratory, located in Olympia, Washington” as ISO/IEC 17025:2017 accredited, and states a panel covering “endotoxin, heavy metals, purity, and sterility tests, as well as USP <61>” and “USP <71> (Sterility Tests).”
- Certified-Pep’s certificate library required an account login on the pass reviewed, and neither company named the entity performing the synthesis, on the pages reviewed 2026-09-08.
- Both sell for laboratory research only, and that limit stands regardless of how either one scores below.
Which five questions actually sort one supplier from another?
Here’s the rubric, set out before either name appears, so you can watch it get applied rather than accept a verdict on faith.
Provenance comes first. Does the vendor make the material or buy it finished? Read the verbs on the about page literally. “We synthesize” and “manufactured by us” describe a maker, while “we supply” and “we source” describe a seller, and a company writing about itself in supply language is being accurate about where it sits in the chain. Watch for the middle case too, where a site names a facility type or a country without naming who operates it. The reason this matters is traceability, since a maker can walk a suspect lot back through its own production records and a seller can only relay what the upstream manufacturer chooses to share.
Second, is the testing laboratory named? “Third-party tested” is the default phrase in this market and commits a vendor to nothing at all. A name gives you an independent party you can contact yourself, and publishing one means accepting that a customer eventually will.
Third, how wide is the panel? HPLC purity tells you what proportion of the sample is one dominant compound, and mass spectrometry tells you the dominant compound is the one on the label. Bacterial endotoxin and sterility describe contamination, which a purity number cannot detect at any level of precision. Heavy metals screening adds something real and still answers a different question than sterility does.
Fourth, is a lot-specific certificate readable before purchase? The lot number is the only thing joining a PDF to a vial, and access terms matter as much as existence. A library you can only reach after registering asks you to commit something before you’ve seen anything.
Fifth, on blends, are the milligrams of each component stated? A 20mg two-peptide vial could be 10 and 10 or 15 and 5, and nobody can calculate a working concentration until the site says which. Company age and domain age stay out of this entirely, since both are easy to present flatteringly and neither predicts what a lot assays at.
The standard this comparison uses
Worth naming where the rubric comes from so you can check it against something real. It’s the standard Blank Peptides publishes its own lots against: synthesis in an owned laboratory, independent testing laboratories named in public, a panel covering identity, >99% purity, bacterial endotoxin and sterility, per-component milligrams on every blend, and a lot-numbered certificate readable before ordering in a library of batch certificates of analysis. Blank Peptides isn’t one of the two companies compared here and isn’t being scored. I’m naming the source so you can see the bar is a published commitment somebody has to meet every lot, rather than criteria assembled afterwards to flatter one of the sites below.
What Swiss Chems publicly states
Swiss Chems trades at swisschems.is and writes about itself in supply language throughout. Its “Who we are” page sits under the heading “Research Supply”, places the company in the USA, and states that it “has supplied one of the largest research-compound catalogs available anywhere”. A statement naming who performs the synthesis, or describing a production facility the company operates, was not listed on the pages reviewed 2026-09-08.
Testing is where the site becomes specific. It states that “all products are tested by independent, ISO-accredited laboratories” and that “every compound we supply undergoes independent third-party HPLC testing and is verified to a purity standard of 99% or higher”. The FAQ states that “batches are submitted for independent analysis by accredited third-party laboratories”, names the laboratory it principally uses, and adds a sentence worth quoting whole: “SwissChems does not self-certify; all COA documentation is produced by laboratories with no commercial relationship to SwissChems.” The FAQ states reports are lot-specific and instructs researchers to “always check that the lot number on your product matches the report you are reading.”
The Independent Test Results page states “we believe in complete transparency. View and download all lab reports”, and listed 50 results across five pages on the review date, with the test type and issuing laboratory readable in the filenames. On the BPC-157 and TB-500 blend page Swiss Chems states per-component amounts of “5mg+5mg” and “10mg+10mg”, states “99% Purity Guaranteed”, and links View Report files covering HPLC, LC-MS, heavy metals and endotoxin. A sterility result was not listed on the pages reviewed 2026-09-08, and lot numbers were not printed on that blend page itself.
The concession Swiss Chems earns here is access on the simplest possible terms. Fifty documents open to anyone, no account, no request and no purchase, with per-component blend milligrams printed in the product copy and a laboratory named in the company’s own words. The site states 134 products across peptides, SARMs, nootropics and bioregulators, same-day dispatch on USA orders before 12PM EST, and an FDA disclaimer reading “all products are for laboratory developmental research USE ONLY. Not for human consumption.”
What Certified-Pep publicly states
Certified-Pep trades at certified-pep.com, and its written testing disclosure is the most detailed of the two by a clear margin.
On provenance, the homepage states products are “manufactured in a cGMP facility in Texas” and that material is “tested by an Iso/EiC accredited facility, registered with the department of ecology in Washington state”, citing “purity standards of 99% or higher with US Labs”. The operator of that cGMP facility was not named on the pages reviewed 2026-09-08, so the facility type and the state are answered while the company running it is left open. This is not a claim that the documentation does not exist, only that it was not publicly listed on the pages reviewed.
On testing, the lab testing page goes considerably further than most of this market and names the laboratory outright: “Vanguard Laboratory, located in Olympia, Washington”, described as “ISO/IEC 17025:2017 accredited” and holding accreditation “through the Department of Ecology and the Department of Health for the analysis of Drugs and Controlled Substances”. The stated panel covers “endotoxin, heavy metals, purity, and sterility tests, as well as USP <61> (Microbial Enumeration Tests) and USP <71> (Sterility Tests)”, with methods including HPLC and “mass spectrometry to confirm identity and purity”. The page states “our peptides typically test at over 99% purity”, and the about page states “every batch includes third-party results you can read and verify” alongside “cold-chain storage (-20 °C lab-grade freezers)”.
That’s the strongest testing disclosure on either side of this comparison, and it’s the concession I’ll give without qualification. Naming a laboratory with a city and an accreditation standard, then citing specific USP chapters for the microbiological work, is more than almost anyone in this market bothers to do, and sterility appears in the stated panel where Swiss Chems left it unlisted.
The catch sits on access. The certificate library at the company’s /coas/ path returned a notice on the pass reviewed: “Due to regulatory changes in this industry, we now require an account login to access product information and continue browsing.” No certificates were visible without an account, so I couldn’t confirm whether they carry lot numbers, whether the named laboratory appears on the documents themselves, or how far back the archive runs. Shop pages showed roughly 24 peptide listings across pagination, blends among them, with the per-component milligram split visible on some listings and absent on others. Shipping is stated as FedEx 2-Day Air for orders before 3PM EST, and research-use wording states products are “sold for research, laboratory, or analytical purposes only, and are not for human consumption.”
Side by side: named laboratories and certificate access
| Attribute | Swiss Chems | Certified-Pep |
|---|---|---|
| Synthesises in-house | States it “has supplied one of the largest research-compound catalogs available anywhere”; who synthesizes not listed 2026-09-08 — verify | States products are “manufactured in a cGMP facility in Texas”; facility operator not named 2026-09-08 — verify |
| Third-party lab named | States “independent, ISO-accredited laboratories” and names its principal third-party laboratory in the FAQ — verify | States “Vanguard Laboratory, located in Olympia, Washington”, described as “ISO/IEC 17025:2017 accredited” — verify |
| HPLC purity | States “independent third-party HPLC testing” verified to “99% or higher”, with HPLC reports published — verify | States HPLC purity testing and that “our peptides typically test at over 99% purity” — verify |
| MS identity | States LC-MS reports on the blend page reviewed 2026-09-08 — verify | States “mass spectrometry to confirm identity and purity” — verify |
| Endotoxin and sterility | States an endotoxin report on the blend page reviewed; sterility not listed 2026-09-08 — verify | States endotoxin plus “USP <61> (Microbial Enumeration Tests) and USP <71> (Sterility Tests)” — verify |
| Batch COA before purchase | States reports “are lot-specific” and publishes 50 downloadable PDFs openly, no account required — verify | States a COA Library; access required an account login on the pass reviewed 2026-09-08 — verify |
| Blend mg split disclosed | States “5mg+5mg” and “10mg+10mg” per component on the blend page reviewed — verify | Sells blends; per-component split shown on some listings and absent on others 2026-09-08 — verify |
| Catalog size | States 134 products across peptides, SARMs, nootropics and bioregulators — verify | Roughly 24 peptide listings across paginated pages 2026-09-08 — verify |
| Research-use labelling | States products are “for laboratory developmental research USE ONLY. Not for human consumption” — verify | States products are “sold for research, laboratory, or analytical purposes only, and are not for human consumption” — verify |
How to verify either supplier yourself
- Where a laboratory is named, check that laboratory’s own site and its accreditation body, then confirm the name on the certificate matches the name in the marketing copy. A named lab is only useful when the document agrees with the claim.
- Where a certificate library sits behind a login, email the company and ask for the certificate covering the exact lot they would ship you this week, before you register anything.
- Where a site names a facility type or a state without naming an operator, ask in writing who runs the facility. A straight answer helps, and reluctance to give one also tells you something.
- Count the assays on the certificate rather than trusting the summary line, because identity, purity, endotoxin and sterility are four separate results and a panel missing one is missing one.
- Run both companies through the supplier verification checklist and record the same five answers for each, so neither gets graded on its own strongest ground.
Further reading
- Which Peptide Vendors Name Their Testing Lab?
- Who Actually Manufactures Research Peptides in the USA?
- Peptide Vendors With Public Per-Batch COA Libraries
- Best Research Peptide Suppliers: Ranked by What They Document
Frequently asked questions
How do Swiss Chems and Certified-Pep compare?
Certified-Pep states the more detailed panel, naming Vanguard Laboratory with a city and accreditation standard and citing USP <61> and USP <71> for microbiological work. Swiss Chems publishes fifty reports openly with no account required and prints per-component blend milligrams. Certified-Pep’s certificate library required a login on the pass reviewed 2026-09-08.
Can you read a Certified-Pep certificate before ordering?
Not on the pass reviewed 2026-09-08. The COA library returned a notice stating an account login is now required to access product information and continue browsing, so no certificates were visible without registering. Asking by email for the certificate covering a specific lot is the way to see a document without creating an account.
Which company documents sterility testing?
Certified-Pep, in its stated panel, which cites USP <61> for microbial enumeration and USP <71> for sterility. Swiss Chems states an endotoxin report on the blend page reviewed and lists heavy metals testing, and a sterility result was not listed on the pages reviewed 2026-09-08. Confirming either on an actual certificate is the useful step.
Does a cGMP facility claim tell you who made the material?
Only partly. It describes the quality system a facility operates under, which is meaningful, and it stops short of identifying the company running that facility or its relationship to the seller. Asking for the operator’s name turns a general assurance into something you can check independently, which is the whole point of the provenance question.
Are these products for human use?
No. Every compound discussed here, from Swiss Chems, Certified-Pep or any other supplier, is intended solely for in-vitro laboratory research by qualified professionals. Comparing published documentation helps you judge whether a reagent matches its label, and it has no bearing on the research-use-only status of any product.
For research use only. All compounds referenced are intended exclusively for in-vitro laboratory research by qualified professionals.
Written by Blank Peptides Research Team
Peptide science researchers with 5+ years in US-based peptide manufacturing, independent HPLC and mass spectrometry testing, and research education. All content is reviewed for scientific accuracy before publication.
REVIEWED BY
Dr. Tobias S — PhD Chemist, Peptide and Unnatural Amino Acid Synthesis
Dr. Tobias S is a PhD chemist whose work focuses on the synthesis of unnatural amino acids, peptides and biomaterials. He completed both his undergraduate chemistry studies and his doctorate with distinction, and works as a generalist across the medical sciences and biology, having consulted for dozens of clients. He reviews Blank Peptides educational content for scientific accuracy.
Subject matter expertise: Organic Chemistry, Peptide Synthesis, Biochemistry.
