Field Guides / Guide 08
How to Read a COA (and Why It's Everything)
Third-party testing is the only quality control that exists in this space. Here's what a real COA shows, how to verify one, and the red flags that mean walk away.
No regulator inspects research peptides. No manufacturing standard applies. The Certificate of Analysis (COA) from an independent lab is the only evidence that a vial contains what its label claims — which makes reading one a survival skill, not a nicety. Independent surveys of this market routinely find purity is usually fine but quantity accuracy is all over the map — vials running from half-filled to wildly overfilled. Both directions are dangerous: underfill means your dose math is wrong low, overfill means wrong high.
What a real COA contains
- The lab's name — and it isn't the vendor. Third-party means independent. Real testing labs are lookupable businesses; many let you verify a report number directly on their site.
- Identity testing (usually HPLC + mass spec) — confirms the molecule is what the label says. The mass-spec readout should match the compound's known molecular weight.
- Purity percentage — 98%+ is the usual bar for legitimate product. Watch what the remainder is when stated.
- Quantity ("mass balance" / fill weight) — the underrated number: does a "10 mg" vial contain 10 mg? This is where surveys find the most cheating.
- Batch/lot number that matches YOUR vial — a COA for some other batch from last year is marketing, not evidence.
- Test date — recent, and plausibly matched to the batch's production.
HPLC vs mass spec, in three sentences
HPLC (high-performance liquid chromatography) separates everything in the vial and shows how much of it is one single substance — that's the purity percentage. Mass spectrometry weighs the molecule and confirms it's the right one — that's identity. You want both on a COA: HPLC proves it's clean, MS proves it's actually the compound on the label — one without the other is half an answer.
The power move: test a vial yourself
Independent labs accept vials from regular customers — you mail one in, they run HPLC/MS, you get the report in days for roughly the cost of a nice dinner. Nobody does this for every order; doing it ONCE for a new source tells you more than a hundred forum reviews, and vendors behave differently when they know their customer base spot-checks. Community-run testing projects publish results the same way — search any vendor's name plus "independent test" before a first order.
How to verify one in five minutes
- Look up the testing lab. Real lab, real website, real address?
- If the lab offers report verification, punch in the report number.
- Check the batch number on the COA against the vial in your hand.
- Compare the stated purity/quantity against the label claim.
- Search the vendor's name + "test results" — communities that send vials for independent testing exist, and vendors that fail get named.
Red flags that mean walk away
- No COA at all, or "testing available on request" that never arrives
- COA with no batch number, no lab name, or the vendor's own logo as the "lab"
- One ancient COA recycled across every product
- Purity claims of exactly "99.99%" on everything (real results vary)
- Prices dramatically below the market — testing costs money; someone skipping it has to win on price
The one-sentence policy
If the current batch's independent COA doesn't exist, the product doesn't exist. Everything else in this library assumes that filter has already been applied.
Research protocols, not a prescription — talk to a physician before touching anything.