What do we check on every vendor?
Every vendor gets the same checks, done the same way, whether or not we earn anything from them. They fall into four groups.
Lab reports. A certificate of analysis, or COA, is a lab report on a specific batch of a product. For each product we sample, we ask four plain questions. Is there a real report for it? Does the report carry the vendor's own name, rather than a supplier's or another shop's? Is a batch number printed on it? And did a lab that's truly independent of the vendor issue it, meaning a real testing business with its own premises and its own clients, sharing no owner, address or website with any vendor? Our guide to reading a COA shows you how to run the name, batch and lab checks yourself before you order. Where an independent testing group publishes its own results on a vendor, we take those in too.
The store and how you pay. We look at how long the website has existed. A young store isn't marked down for it, it just has no track record yet, and we say so. We also look at which payment methods checkout really accepts, and we favor ones that come with buyer protection, like credit cards, covered PayPal purchases and the major wallets. We get as far as the payment step to see what's offered, because card logos in a footer can outlive the card processing behind them. Smaller details, like free shipping or same-day dispatch, can earn credit, and not having them never counts against a vendor.
How the vendor behaves over time. We read what customers say publicly, on review sites and in community discussions, and we notice when a vendor draws a pattern of complaints. We also look at how many different peptides it carries and which vendors PPL members save as favorites. A vendor nobody has written about isn't penalized for the silence.
Price level. We compare each vendor's prices with the rest of the market. A lower-priced vendor can earn some credit, and a higher-priced one is never marked down for it. We also record prices every day, and a sudden swing gets a closer look from a person, although price history doesn't feed the label itself.
If a source simply has nothing on a vendor, we treat that as missing information, not bad news. What counts against a vendor is something we checked and found lacking. And one strong signal isn't enough on its own. A vendor needs several kinds of evidence agreeing before it can reach the top label.
What does each confidence label mean?
A label tells you how much evidence stands behind a vendor. It isn't a score, and the site never shows letter grades or numbers. There are five.
High confidence. Several kinds of evidence line up. The products we sampled had real, batch-specific lab reports with the vendor's own name on them, and the store, payment and track-record signals point the same way. It's the strongest label we give, and it's still not a promise about any single vial.
Moderate. There's real evidence here, along with gaps or mixed signals. A vendor might have solid lab reports but little public track record, or good reviews and lab reports that are missing a batch number.
Low confidence. The evidence is thin, or what we found points the wrong way, such as missing or mismatched lab reports, poor results from an independent testing group, or a pattern of complaints.
New vendor. The store is too new to have a track record. This isn't a mark against it. We label it separately so a young store isn't lumped in with a weak one, and it can move up as evidence builds.
Unrated. We haven't checked enough yet, and it's sitting in our vetting queue. A vendor can be listed with prices while still unrated, and unrated is not negative.
Why isn't the cheapest price always the High confidence pick?
A price tells you what a vendor charges. A confidence label tells you how much evidence we have that the vendor delivers what its listing says. Those are two different questions, so they don't always point at the same store.
That's why peptide pages show two lowest prices side by side, each labeled: the lowest among High confidence vendors, and the lowest overall. When the cheapest vendor overall is Moderate, new or lower-confidence, the two numbers differ. The gap is what the extra evidence costs you, and sometimes it's small. Whether it's worth paying is your call, and now you can see it. If no High confidence vendor lists a compound, the page says so instead of quietly picking someone else.
A low price can't buy a higher label, and a High confidence label doesn't make a vendor the cheapest. You can compare both in the app or on our vendor pages, and our guide to buying safely covers what to do with the answer.
How do COA spot checks work?
We don't take a vendor's word that its products are tested. We go and look. For each vendor we pick a random sample of about 20% of its tracked products and check, on the vendor's own site, whether each one has a real lab report for a specific batch. Then we run the four questions above on every report we find.
A product with no report we can find is recorded as checked and not found, and that counts. If we couldn't reach something, say it sat behind a login or came in a format we couldn't open, we record it as not checked. That's a different thing, and it doesn't count against the vendor. When a sample is too small to mean much, we don't lean on it.
It's a sample, and we'd rather say so than imply more. A clean result on the products we picked is good evidence. It isn't proof about every product in the catalog.
How does our affiliate link work?
Some links on the site are affiliate links, which means we earn a commission if you buy through them. We show the best public code for a vendor even when it isn't ours. If a vendor is running a better public discount than our code, that's the one you'll see.
An affiliate relationship doesn't change a vendor's label or where it appears, and no vendor can pay for a better one. The full version is in our affiliate policy.
What don't we publish, and why?
We don't publish scoring weights, thresholds or the raw data behind a label. If we printed exactly how much each check counts and where the lines fall, the quickest route to a better label would be tuning a store to the formula instead of doing the real things, like posting genuine batch reports. Keeping the formula private keeps the label about the vendor. Everyone is held to the same one.
What we do share is this page: what we check and what each label means.
How do vendors ask for a correction or a listing?
Vendors can write to partners [at] peptidepricelab.com. If something on your listing is wrong, tell us what, and send whatever shows it, like a lab report with a batch number, a page on your site or a payment option we missed. We'll re-check it and update the listing if it holds up. If you'd like to be listed, that's the same address. Being listed isn't an endorsement, and a request doesn't move a label on its own. Evidence does.
Readers who spot a mistake anywhere on the site can write to editor [at] peptidepricelab.com.
What can't our labels tell you?
A label reports what we could and couldn't verify on the day we checked. It isn't a judgment of anyone's character, and we don't call a vendor a scam. A low label means the evidence is thin or lacking, and that's all it means.
A lab report describes a batch, not necessarily the vial that ships next month. A sample is a sample. Labels change as new evidence comes in, so look at the current one before you order, and read the lab reports yourself too.
Everything we track is sold for research, and the big human trials haven't been run yet. You knew that already. It's why you're reading the fine print.
