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Buying smart

Purity isn't the same as the right amount

Why a 99% pure vial can still be a bad vial, and how lab-test scores account for it.

99.7% pure6.1 mg in a 10 mg vial98.9% pure10.2 mg in a 10 mg vialPurer isn't fullerfill = measured amount

Vendors love to advertise "99% purity". Purity only describes the share of the contents that is the target peptide. It says nothing about how much peptide is in the vial.

A vial can be 99.5% pure and contain 6 mg instead of 10 mg. It can also be overfilled: 13 mg in a 10 mg vial is common, and it matters if you calculate amounts from the label.

That's why Finnrick's score, which this site shows for every vendor, requires both purity of 99.5% or more and a measured amount within ±35% of the label. On COAs, look for the measured milligrams, not only the purity percentage.

Key points
  • Purity = how clean; quantity = how much.
  • Underfilled and overfilled vials both throw off your numbers.
  • Look for measured mg on lab reports.

Quick check

What does a purity of 99.5% tell you?

Vendor scores · How scores work

General education, not medical advice. Nothing here recommends using any compound or amount.