How to Read a Peptide COA: A Real Report, Field by Field

Research Guide · Quality

How to read a peptide certificate of analysis (COA)

A certificate of analysis is the single most useful document a research peptide supplier can give you, and the most misunderstood. This guide walks through a real third-party report, field by field, and ends with a checklist you can use on any supplier's COA.

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The example report

We'll use an actual report: BPC-157 10 mg, lot B26C211, tested by Vanguard Laboratory in Olympia, Washington and reported on March 23, 2026. Open the full PDF and follow along.

1. The header: who tested what

Laboratory name and accreditation. A named lab with an address, phone and email. This report cites A2LA Certificate #6377.01.01, which lists the tests the lab is accredited to run under ISO/IEC 17025. You can look the certificate up on A2LA's public directory.
Report To. Who sent the sample to the lab. This is often the manufacturer or distributor rather than the store you buy from, so don't be surprised to see another company's name. Ask the supplier how that party connects to the product you're buying.
Compound and quantity. What the sample is supposed to be, and the amount on the label (here, BPC-157, 10 mg).
Laboratory ID. The lab's own tracking number for the sample (here, V260305-14 004). Labs can confirm whether a report with that ID is genuine, which is the simplest defence against an edited PDF.
Lot number and date reported. Which batch was tested, and when. A report that is years old, or has no lot number, tells you little about what is shipping today.

2. The results: three numbers that matter

Analysis	Method	Result	What it means
Chromatographic purity	HPLC-UV/VIS	>99.80%	The share of the sample that shows up as the main peak, versus impurities. ">" means the result sits above the method's top reporting limit. Research grade is usually 98% or higher.
Quantity	HPLC-UV/VIS	10.33 mg	How much peptide was actually in the vial versus the 10 mg label. A small overfill (here, about 3%) is normal; a large shortfall is a red flag.
Endotoxins	LAL	Pass	A test for bacterial contamination. Chemical purity and endotoxin are different things: a sample can be pure peptide and still contaminated, so you want both.

3. The fine print most people skip

Near the bottom, this report says the results "relate only to the portion of the sample(s) tested," and that the lab "did not observe or participate in the sample selection process" and cannot confirm the sample represents the whole lot. That wording is standard, and honest. It means a COA proves what was in the sample the lab received, not what is in every vial. How often a supplier tests, and whether the tested lot matches what ships, is what closes that gap.

4. What this kind of report doesn't tell you

HPLC measures purity and quantity, but on its own it doesn't confirm the molecule's identity. Identity testing is usually done by mass spectrometry (LC-MS or MALDI-TOF), which confirms the molecular weight matches the expected compound. When a supplier offers both, that's a stronger record. When it doesn't, it's a fair question to ask.

A 7-point COA checklist

The lab is named, contactable and accredited, and the accreditation can be looked up.
The report has a lab sample ID you could ask the lab to verify.
The lot number and date are present and recent.
Measured quantity is close to the label claim.
Purity is stated with its method (HPLC), not just a round number on a product page.
Endotoxin was tested, not only purity.
Each product has its own report. The same PDF reused across products, or across years, is a warning sign.

See our reports

Every third-party report we publish is listed in our lab report library. For a broader checklist on choosing a supplier, see how to choose a research peptide supplier.

All products are sold for laboratory and in-vitro research use only. Not for human or veterinary use.

This page is general educational information about research materials. All products sold by Ageless Peptides are for laboratory and in-vitro research use only. They are not drugs, supplements or food, are not for human or veterinary use, and are sold only to adults 21 and older.

How to Read a Peptide Certificate of Analysis (COA)