About the data

About the data: every figure on PepAssess comes from a vendor's own website or from the lab that tested its product, and every figure is dated. Last full update November 6, 2026.

How the data is collected

1. Finding vendors. Other peptide directories, search results, domain-registration records and community discussion are used only as leads. A vendor is listed only if its site has a working cart or checkout.
2. Reading the vendor's site. Each site is read directly — including pages built by scripts — for its lab-results page, named labs, company name, address, email, phone, refund and shipping policies, payment methods, research-use labeling and product catalog. The domain's registration date comes from the domain registry.
3. Reading every lab report. Each certificate (PDF or image) is read for the peptide, lot or batch number, the tests run (purity by HPLC, identity by mass spec, endotoxin, sterility) and the date printed on the report. Scanned certificates are read by text recognition, and QR codes are decoded. The same certificate posted at several sizes counts once.
4. Checking each report with the lab. The report's code, QR link or batch number is looked up in the issuing lab's own public records. A report served from the lab's own website counts as confirmed. Only confirmed reports earn the lab-transparency points.
5. Comparing prices. Product prices are read from each catalog and turned into a price per mg, then compared with the typical price for the same vial size of that peptide: the middle price among the shops selling that size, when at least five do. A shop's overall price comparison averages KLOW, GLOW, Wolverine, GHK-Cu, NAD+, KPV, Retatrutide, Tirzepatide and BPC-157. Prices in other currencies are left out of the typical price.

The method: what is scored (100 points)

Each vendor gets an Evidence Score from 0 to 100, built from fixed checks: the same bar for every vendor, never ranked against other vendors. The score reflects what a vendor publicly shows. It measures observable evidence and transparency, not whether any product is safe, pure or effective. Each vendor profile shows which checks it met.

Lab transparency: confirmed with the lab

A lab report on a vendor's own site is the vendor's claim. It counts only once it is matched to the issuing lab's own public record: the lab's lookup page, the report hosted on the lab's website, or the lab's published registry. Copies of the same report count once. The first confirmed report earns 10 points, the second 5 more and the fourth 5 more. A lab-confirmed endotoxin report earns 5. Validation experience earns 15 at 10 confirmed reports. A vendor whose website is under a year old reaches the fourth-report step at 2 reports and earns 5 of the experience points at 5 reports.

Every lab lookup is tested with a made-up code before it counts; a lookup that would confirm a fake earns nothing. Reports from labs with no public record (email-only, login-only or no lookup at all) can't be confirmed, so they earn none of these points.

Batch/lot lookups, where you enter your vial's lot number to see its report, earn the "publishes lab reports" and lot-number checks but not recency or lab confirmation, because nothing is visible before you buy.

Evidence coverage

Shown separately from the score. 100% means the vendor's website could be read directly. Some stores sit behind age or research-access gates or block automated visits; those show lower coverage, and their score reflects only what could be seen. If a vendor's reports couldn't be read, its profile says so: that is a gap in our reading, not necessarily theirs. Social media popularity is not scored.

Not yet measured

Whether the measured amount matches the label; weighting reports by each lab's own track record; and refund terms. They will be listed here when they count. The method on its own is on the methodology page.

Rules the data follows

• A report's date is the date printed on it, never its upload date or file name.
• A report found once stays on the vendor's record, even if its page is later moved or taken down.
• A blend (GLOW, KLOW, BPC-157 + TB-500 …) is filed as its own peptide, not under its first ingredient.
• Coupon codes are listed only with their discount amount.
• Shops can send corrections or missing documents to hello@pepassess.com; every submission is checked against the source.

How often it is updated

Vendor sites, lab reports, lab checks and prices are refreshed in a full update, about once or twice a week. Each profile and page shows the date its data was last checked.

Citing PepAssess

Please cite figures with their date — for example: "PepAssess counted 3,788 peptide lab reports confirmed by the testing lab as of November 6, 2026." A plain-text brief for AI assistants is at /llms.txt.

Put it to use: current peptide coupon codes, the lowest peptide prices with a code, and sellers with lab reports for Retatrutide, Tirzepatide and BPC-157.