Where the money goes
Samples, shipping, and accredited lab time.
A single report is more expensive than it looks. We pay retail for the product like any buyer, cover temperature-controlled shipping both ways, and pay an ISO/IEC 17025-accredited lab for HPLC, and where needed mass spectrometry and additional safety panels. None of that is free, and none of it is sponsored.
A basic purity and quantitation report runs about $235 all in: the vial, shipping, and accredited lab time. Adding mass-spectrometry identity confirmation pushes it past $550, because it needs a second vial. A full panel with sterility, endotoxin, and heavy metals runs about $700, since the sterility test alone requires an unopened third vial.
Reader support, memberships and one-time contributions, is what lets us test more vendors, more compounds, and re-test the ones that change. There is no vendor on the other end of this page, and there never will be.
A test means nothing if the seller got to choose the sample, or got to fund the tester. Ours never do.