How to check a peptide seller yourself, in ten minutes.

Peptide Chooser editorial team. Checked 2 Nov 2026.

Short answer

Five checks take about ten minutes: find the shop's newest lab report and its date, search the FDA's warning letter list for the shop's name and web address, look the company up in a state business registry, read its terms and refund pages, and see when its prices last changed.¹² None of them tells you that a product is safe; a research-use vial is not approved for use in people whatever the checks show.³

Why check a seller yourself?

Research-use shops sell products that no regulator checks before they are sold.⁴ You cannot test what is in a vial at home, but you can check public facts about the shop. These are the same five facts we collect.¹

Step 1: Is there a recent lab report?

Look for a certificate of analysis (COA) on the product page or a "lab results" page. Check three things:

the date: we count a report only if it is from the last 12 months;¹
the lab's name, and whether it is a lab outside the shop;
whether the batch number matches the product you would get.

A report covers one batch, tested once. Our guide on how to read a COA shows what each line means.

Step 2: Has the FDA sent it a warning letter?

The FDA publishes its warning letters in a searchable list on fda.gov.² Search for the shop's name, then for its web address, because company names repeat and a letter may name the business behind the shop. Our letters page lists the letters to peptide sellers, compounders and online clinics.

A letter is the FDA's formal notice, not a court ruling; read it, and note its date.⁵

Step 3: Is there a real company behind it?

Look at the shop's terms page or footer for a company name and state. Then search that state's business registry, for example Florida's or Delaware's. A match tells you the company exists and whether it is active; it says nothing about the product.

Not finding it does not prove the shop is fake: it may be registered in another state. We match only with high confidence and do not search every state yet.¹

Step 4: Does it have terms and a refund page?

Look for a terms page and a privacy or refund page. Read the refund page: what happens if a package does not arrive or a vial is damaged? Having these pages says nothing about what they promise.¹

Step 5: Are the prices current?

A shop whose prices have not changed in a long time may not be keeping its site up. We count prices as fresh when we saw one in the last 30 days.¹ Work out the price per mg yourself: the price divided by the amount in the vial.

Which warning signs should you look for?

A lab report with no date, no lab name or no batch number.
The same lab report image on many different products.
No company name or address anywhere on the site.
A "research use only" label next to advice on how to use the product on yourself.
A price far below what other shops charge: our goal pages show the middle price per mg for each peptide.

One sign is not proof of anything, but several together are a reason to stop.

What the checks cannot tell you

Whether the product is safe or works. The checks are about the shop, not the vial.
Whether the product is approved. A research-use vial is not approved for use in people, whatever the shop's checks show.³
What the law means for you as a buyer. The FDA's letters go to sellers; a lawyer can answer for your state.

Can we do this for you?

Our seller pages do these five checks for every shop we track and show the result with its date. Our How we rate page has the rules, and our guide on how we check sellers gives an example of each check.

None of this is medical or legal advice.

What to do next

See all sellers How we check sellers

Sources

Peptide Chooser, How we rate peptide products and sellers
FDA, Warning Letters (the searchable list), current as of 27 Oct 2026: https://www.fda.gov/inspections-compliance-enforcement-and-criminal-investigations/compliance-actions-and-activities/warning-letters
Drugs@FDA, searched through openFDA for BPC-157, GHK-Cu (also as copper tripeptide and prezatide) and TB-500 (also as thymosin beta-4): no approved product, 2 Nov 2026: https://www.accessdata.fda.gov/scripts/cder/daf/index.cfm
FDA, Development and Approval Process: Drugs: https://www.fda.gov/drugs/development-approval-process-drugs
FDA, About Warning and Close-Out Letters, current as of 20 Mar 2024: https://www.fda.gov/inspections-compliance-enforcement-and-criminal-investigations/warning-letters/about-warning-and-close-out-letters