How to Read a COA in Under 60 Seconds

A Certificate of Analysis (COA) doesn't have to be complicated. Here's how to quickly understand what you're looking at.

1Check the Product Name

Product: Tesamorelin 10mg

This tells you exactly what the lab tested. Ask yourself: does this match the vial in your hand? If not, stop there.

2Match the Lot Number

Lot: CPTESA1026041605

Think of this as the batch number. The lot number on your vial should match the lot number listed on the COA. If it doesn't, the COA may not belong to your product batch.

3Check the Purity

Purity: 99.03%

This tells you how much of the sample was actually the intended peptide. 99.03% = Tesamorelin, 0.97% = everything else combined. Most people like to see purity above 98%.

4Check the Net Content

Net Content: 11.07 mg

The vial is labeled as 10 mg, but testing found 11.07 mg. The vial contained slightly more peptide than advertised, which is called an overfill. Small variations, over or under, are not unusual.

5Confirm the Identity

Identity (LC-MS): Confirmed

This answers the question: is this actually what it says it is? In this case, yes, the testing confirmed it was Tesamorelin.

6Look for Endotoxin Testing

Endotoxin Replicate 1 & 2: Pass

Endotoxins are bacterial toxins that can remain behind during manufacturing. "Pass" means the sample met the laboratory's acceptable limits. Not every COA includes this, so it's a nice additional layer of information.

7Don't Panic Over the Graphs

Chromatogram + Mass Confirmation

The chromatogram is used to calculate purity, one tall, clean peak is generally what you want to see. The mass confirmation proves the molecular fingerprint of the peptide. You don't have to understand every number on these graphs.

The 30-Second COA Checklist

  • Product matches your vial
  • Lot number matches your vial
  • Identity says "Confirmed"
  • Purity is high (many look for 98%+)
  • Net content is close to the label claim
  • Endotoxin testing says "Pass" (if included)

Bottom line

A COA isn't about finding perfection, it's about transparency. You're simply asking four questions:

  • Did they test the right product?
  • Was it actually what it claimed to be?
  • How pure was it?
  • Did the amount match the label?

If you can answer those four questions, you know how to read a COA.

For educational and research purposes only. Not medical advice. The example shown is a real Certificate of Analysis from Coffee & Peppers, used with permission.