Two ways in

You should not have to search the whole internet for a fair price on something that was actually tested.

So we publish both halves and let you check them. What things cost is read from every seller we can reach, refreshed nightly, by the same computation that sets our own price. What is in the vial is an independent lab result and a batch certificate, not a sentence claiming one exists.

• Price RUO Radar reads published prices across the market and normalises them to price per milligram, which is the only axis on which two sellers of different sizes can be compared at all. The numbers are open, including the ones where we are not the cheapest. See the price index
• Quality Every batch is sent to an independent third-party lab, and the certificate for the exact batch in your hand resolves from the code on the bottle. 46 batches on this brand carry an independent lab result and a certificate you can open from the code on the bottle. Read the lab results