Help centre
Four pages. Between them they cover everything you need to use the site properly, and one of them you should read before making any claim about a supplier.
What separates a question that gets answered from one that gets closed, with worked before-and-after examples.
Help2026-07-30What counts as a source here, for clinical claims and for supplier claims, and what happens when a claim has none.
Help2026-07-30Every badge, its threshold, and why the thresholds are published.
Help2026-07-30Scope, limits, and a plain statement of what this site is not.
Help2026-07-30How the Q&A format works and how it differs from a forum. Start here if the site feels unfamiliar.
Orientation2026-07-30Frequently asked, briefly
- Can I post?
- Not currently. This is a static archive of 5.2k questions and 20k answers. The norms are documented because they explain why the archive reads the way it does.
- Why are vendor storefronts linked, and what does the marking mean?
- Because a reader checking a claim should be able to reach the source in one click, and because hiding the address does not make the purchase safer. The link is marked nofollow and sponsored: we have no relationship with any supplier, are paid nothing, and a link is not an endorsement.
- Are the ratings on the vendor pages measurements?
- No. They aggregate contributed opinion. The columns that carry information are the documentation-practice ones and the independently obtained test results.
- Why is the same purity figure reported differently by two laboratories?
- Method differences, principally detection wavelength and gradient slope. A spread of half a per cent to a per cent on the same vial is normal. The COA reader quantifies the contributors.
- Is any of this medical advice?
- No, and the disclaimer says so at greater length. Research-use-only compounds are not approved for human use.
- How do I cite a page here?
- Cite the specific question URL, not the site. Contributions are licensed CC BY-SA 4.0.
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