Vendor checklist
How to verify a peptide vendor
Verifying a peptide vendor means checking what independent labs found in its vials, not what the shop says about itself. Look up any peptide vendor's lab results below: Peptide Vendor Reviews holds 12,369 independent tests across 491 vendors, each with its store status. For a shop we haven't covered, use the seven checks below.
Or browse the peptide vendor list, the peptide purity test results, the closed peptide vendors, or get your own vial tested.
Find independent tests of that vendor
Look for lab results on vials bought from the vendor by someone else. Its own certificates don't count: the shop picks the batch and the report. Search the vendor in our vendor reviews to see every independent test we hold, with the original certificate.
Confirm the certificate is real
A real certificate names the lab, the batch or lot number, the test date and the method. Match the batch to the label on your vial. Many labs let you confirm a report on their own site with a code printed on it. An edited PDF can't pass that check.
Check the quantity, not just the purity
A vial can be 99% pure and still hold far less than the label says. In the 11,575 vials we have measured, 15.4% held less than 90% of the labelled amount. Look for “tested quantity” next to the label amount.
Check the identity result
Identity testing confirms the vial holds the compound on the label. 691 of 12,288 samples we hold (5.6%) failed it. Purity alone can't catch this, because it measures the sample against whatever reference was used.
Look at purity across batches
One good result is a start, not a record. 6.1% of 11,607 purity results tested below 98%. Prefer vendors with several recent tests across different products. How we grade vendors explains the A–E scale.
Check how you pay and who you're paying
Card payments can be disputed; crypto and bank transfers usually can't. Check that the site names a business and a way to reach it, and how long the domain has existed. None of this proves quality, but a missing basic is a reason to slow down.
Still unsure? Test a sample yourself
The only result that covers your vial is a test of your vial. Independent analytical labs will test a mailed sample for identity, purity and quantity, usually for a flat fee per test. Ask for HPLC purity plus mass spectrometry identity, and keep the vial's batch number with the result.
Red flags
- Only their own certificates, with no lab name, batch number or date you can check.
- A certificate whose batch number doesn't match the vial you received.
- Payment only by crypto, Zelle or gift card, with nothing you can dispute.
- No company name, address or working contact details on the site.
- Prices far below every tested competitor for the same compound.
- Reviews that are all five stars, undated, or tied to a discount code.
What a passing vendor looks like
Several independent tests across different products, recent dates, identity passes, fills close to the label and purity at 98% or above. On our reviews that shows as a Strong lab record.
Research peptides are sold for laboratory use only. Nothing here is medical advice.