The VendorVerify blog
What the lab data shows
How to read peptide lab reports, spot a fake, and make sense of what independent lab tests actually find. Written from the data, not from vendors.
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What the lab data showsTirzepatide test results: what 788 lab-tested vials showMore research tirzepatide has been lab tested than any other compound in our data. Here's what 788 independently tested vials actually show, vial size by vial size.Sep 28, 2026
What the lab data showsRetatrutide test results: what 336 lab-tested vials showRetatrutide's purity numbers are some of the cleanest in our data. Its fill amounts are a different story. Here's what 336 independently tested vials show.Sep 28, 2026
What the lab data showsTesamorelin test results: what 32 lab-tested vials showTesamorelin is far less tested than the GLP-1 compounds. Here's what 32 tested vials show, and why the small sample matters.Sep 28, 2026
What the lab data showsUnderdosed peptides: which compounds miss the label most (and which are overfilled)Being short of label is less common than being over it, but it happens, and some compounds run short far more than others. Here's what 1,441 measured vials show.Sep 28, 2026
What the lab data showsEndotoxin and sterility in research peptides: what independent lab tests foundA clean purity number says nothing about endotoxin or sterility. Here's what those separate tests measure, and what 219 buyer-commissioned results actually showed.Sep 28, 2026