Guide · 6 min read

How to verify a Janoshik peptide report

By the PeptideCOACheck team · Last updated November 2, 2026 · How we check

Janoshik is one of the most widely cited testing labs for research peptides, which also makes its reports a target for editing. The good news: the lab gives you a free way to check any report against its own records. Here's how to do it, and what a match does and doesn't prove.

What you need before you start

According to Janoshik's own help center, a report can be verified only if it carries two identifiers:

• A task number, printed at the top of the report.
• A unique key, printed at the bottom of the report.

If either one is missing, the report can't be verified. That is common with cropped screenshots on product pages, so ask the seller for the complete, original report. Some reports also carry a QR code that takes you straight to the lab's copy.

How to verify a Janoshik report, step by step

1. Get the full report. A PDF or full-page image from the seller, not a crop of the results table.
2. Open the lab's verification page. Go to janoshik.com/verification yourself. Don't use a "verify" link the seller sends you, which could point somewhere else.
3. Enter the task number and unique key. Type the key in capital letters, as Janoshik instructs. Or scan the QR code, then check that the page it opens is on janoshik.com.
4. Open the stored report. If the identifiers are genuine, the page confirms it and offers an "Open report" button. Click it.
5. Compare the two line by line. Product name, sample description, purity, mass result, quantity and dates should match exactly. Janoshik's rule is strict: a report is legitimate only if it matches the version stored in its system. Any change, even one digit, means your copy has been altered.
6. Check the numbers themselves. Enter the mass, purity and dates in the free COA checker to confirm they make sense for the compound.

What a verified report proves, and what it doesn't

A successful verification is strong evidence on one narrow point: Janoshik tested a sample and reported these results. It does not tell you:

• Whether your vial came from that sample's batch. Match any batch or lot details on the report to your vial, and look at the test date. A report from two years ago says little about this month's stock.
• Who chose the sample. When a vendor sends its own sample, it decides what gets tested. Tests of samples bought anonymously from the open market are stronger evidence.
• Anything that wasn't tested. If the report shows only purity and identity, it says nothing about endotoxin, sterility or heavy metals.

Red flags when checking a Janoshik report

• The task number or unique key has been cropped, blurred or covered.
• The seller won't share the full report, or only sends it after you buy.
• The stored report differs from the seller's copy in any field.
• The same task number appears on COAs for different products or batches.
• The "verification" link the seller provides opens a page that isn't on janoshik.com.

For a fuller list of warning signs, see COA red flags and how to tell if a COA is fake.

Using Janoshik's public results

Janoshik also runs a public results database at public.janoshik.com, where clients can publish their reports. It's useful for seeing what typical results for a compound look like, or whether a vendor's products have been tested by other buyers. Remember that publication is the client's choice, so the database shows the reports people wanted seen, not every test.

If you want stronger evidence

The only direct evidence about your own vial is a test of your own vial. Janoshik and other labs accept samples from individuals. See third-party peptide testing explained for how that works, and net peptide content for why a quantity test matters as much as purity.

PeptideCOACheck is not affiliated with Janoshik Analytical. Educational content only. Not medical advice.