Quarterly
The Annual Purity Report
Once a year, we order from every major US supplier and HPLC-test every sample under blinded conditions. Subscribers get the full report — chromatograms, scoring, methodology — before it goes public.
Subscribe — Free
The independent peptide newsletter — written for researchers, not retailers.
Independent HPLC purity data, supplier evaluations, and compound briefings delivered to your inbox. No advertorials, no affiliate-driven rankings, no fluff.
Free forever. Unsubscribe in one click. We never sell your email.
What lands in your inbox
Monthly
New supplier evaluations
When a supplier launches, shuts down, or has a quality incident, we test and write about it. Subscribers get the analysis the same day we publish.
As needed
Research compound briefings
Deep-dives on emerging compounds (Retatrutide, the next-generation peptides). What the literature actually shows, who is sourcing it well, where the counterfeits are.
Never
Sponsored content
No supplier pays for placement in our reports or our inbox. Affiliate links are disclosed and never affect scoring. If we ever break this, the inbox is the first place we lose readers.
The only newsletter we read in this space. Honest data, no sponsor-driven nonsense.
Common questions
- How often will you actually email me?
- Once a month minimum, twice a month maximum. We never email more than that. When we do publish a new supplier evaluation or a quarterly report, we send the email the same day it goes live on the site.
- Do you sell my email to anyone?
- No. We use Resend to send the emails and that’s where the list lives. We don’t share, sell, or resell it.
- Are there affiliate links in the emails?
- Yes, occasionally. They are always disclosed. They never affect which suppliers we recommend, what we publish, or how we score products. Our supplier rankings are determined by blinded HPLC results plus our six-criterion rubric — read the methodology.
- Can I read past issues before I subscribe?
- Yes — every published article is free to read at /articles. The newsletter is a notification system, not paywalled content.
- What if I want to unsubscribe?
- One click, in the footer of every email. We don’t make it hard. We’d rather have 2,000 readers who want to be here than 20,000 we annoyed into staying.
Last thing
The 2026 Annual Purity Report is the first email new subscribers receive. It is free.
Eight US suppliers. Thirty-eight samples. One blinded analytical lab. The full report — chromatograms, scoring, anonymized failure cases — delivered the moment you sign up.
Free forever · No sponsorship
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