Testing Scores Explained

Each retailer is scored out of 7 standard Certificate of Analysis (COA) tests. Here's what each one means.

The 7 tests at a glance

Net Content Net Purity Identification Endotoxins Sterility Heavy Metals Conformity

1Net Content

What it measures: Measures how much active peptide is actually in the vial versus the amount printed on the label.

Why it matters: Confirms you're getting the quantity you paid for — under-filled vials mean less material than advertised.

2Net Purity

What it measures: The percentage of the sample that is the intended peptide versus impurities and related substances, typically by HPLC.

Why it matters: Higher purity means fewer contaminants and byproducts; low purity can signal degraded or adulterated material.

3Identification

What it measures: Confirms the sample is genuinely the labeled peptide — usually by mass spectrometry matching the expected molecular weight.

Why it matters: Guards against mislabeled, substituted, or counterfeit compounds.

4Endotoxins

What it measures: Measures bacterial endotoxin levels (LAL assay).

Why it matters: Elevated endotoxins indicate bacterial contamination during manufacturing or handling.

5Sterility

What it measures: Checks the vial for microbial growth (bacteria and fungi).

Why it matters: Confirms the product was filled and sealed without microbial contamination.

6Heavy Metals

What it measures: Screens for toxic heavy metals such as lead, arsenic, cadmium, and mercury.

Why it matters: Flags contamination introduced by raw materials or the manufacturing process.

7Conformity

What it measures: An overall check that the Certificate of Analysis matches the specific product, lot, and labeled specifications.

Why it matters: Ties the certificate to the exact batch you receive, rather than a generic or unrelated COA.

How the score works

A retailer's testing score is simply the number of these seven tests it passes, shown as X/7 next to its name. Hover the score on any product card to see exactly which tests it passes or fails and which third-party labs it uses. More passed tests and reputable labs generally indicate a more transparent vendor.

Third-party testing labs

Independent laboratories that vendors commonly use to test their peptides. The specific lab can vary by batch — always check the COA for the lot you receive.

Testing data is provided by retailers and may change between batches. Always verify the current Certificate of Analysis with the vendor.