I keep a mental list of peptide vendor red flags, and it's gotten longer every year. Not because scammers got smarter. Because they got lazier, and more people are buying without checking.
Here's the whole list, organized by how fast each one should make you close the tab. Some are dealbreakers on their own. Others add up.
Quick note before we start: these are research compounds, not FDA-approved drugs, and they're sold for laboratory research only. Any vendor who forgets that is already waving a flag.
Dealbreaker peptide vendor red flags
These are the ones where I don't need a second reason.
No COA at all. If a vendor can't show a certificate of analysis, you have no idea what's in the vial. There's nothing to discuss.
COA with no lot number or no lab name. A report that isn't tied to a batch and isn't signed by a lab is a picture, not a test. It could be recycled from another vendor or made from a template.
The same COA on every batch. Real test results vary slightly from lot to lot. If the purity number never changes, nobody is testing.
Crypto-only payment. Legitimate businesses can take a card. Vendors who only accept crypto are often avoiding chargebacks, banking scrutiny, or both. Once your payment goes through, you have no recourse.
Dosing advice on the product page. This one surprises people. A vendor selling research compounds should not be telling you how to use them. If they are, they're either careless about the law or don't care about you. Either way, they're a liability.
Serious warning signs
Two or more of these and I'm out.
"Testing available on request." Translation: we'll send you something if you push hard enough. Vendors who are proud of their lab work publish it before you buy.
No mention of a third party. "Tested in-house" means the seller graded their own homework.
Purity claims with no identity check. HPLC gives a purity percentage, but only mass spectrometry confirms the compound is what the label says. A vendor who skips identity testing is skipping the hard question.
No cold chain. Peptides degrade with heat. A vendor who ships in a plain envelope with no cold pack, and doesn't mention shipping conditions anywhere, isn't protecting what you paid for.
Vague or missing shipping times. "Ships soon" is not a timeframe. Legitimate domestic vendors tell you what to expect.
Prices way below everyone else. Real synthesis and real testing cost money. If one vendor is half the price of the market, the savings came from somewhere.
Softer signals that add up
None of these alone proves much, but they tell you what kind of operation you're dealing with.
- A website with no company name, address, or contact beyond a form.
- A domain registered a few months ago.
- Product photos that also appear on three other vendors' sites.
- Grammar and spelling that suggest nobody proofread the compound names.
- A flood of brand-new Reddit accounts saying the vendor is "g2g."
- Refund and reshipping policies that are missing or contradictory.
- Testimonials with personal results. Serious research vendors don't publish those.
The context that makes all this matter
The peptide space has been under heavy enforcement pressure since 2024. FDA warning letters went out. Several vendors were reportedly raided. Paradigm Peptides' founders were reportedly prosecuted. Peptide Sciences reportedly closed in March 2026. Lilly and Novo have sued sellers of tirzepatide and semaglutide products.
Vendors that cut corners on testing and transparency are the ones most likely to vanish overnight, taking your order and your recourse with them. The red flags above aren't just about product quality. They're about whether the company will exist next month.
What the green flags look like
It helps to know what you're comparing against. Exactide checks the boxes that matter: third-party testing on every batch, identity, purity, and sterility all verified, purity confirmed at 99% or higher, and a batch-specific COA published before the product ships. Domestic orders go out in 2-4 business days, cold-shipped in discreet packaging, with free domestic shipping over $150. They take standard payment methods, and they don't make you chase them for lab work.
Hold every vendor to that standard. The ones who can't meet it have told you what you need to know. If you want a baseline for comparison, start at Exactide.
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