The short answer
On the axis that matters to us, published per-batch lab data, Onyx Biolabs is legit and transparent. We grade them Grade A (Established), and we currently track 20 of their products. Onyx publishes a per-batch Certificate of Analysis (COA) for products, the certificates are run by a third-party lab, and the purity figures we have seen are high and consistent across their catalog.
To be fair and clear: we do not sell peptides and we are not Onyx. We aggregate prices and lab data and link out to vendors. So this is not a hype piece. A Grade A here means Onyx does the transparency work most buyers care about: they show their batch testing, and their pricing on the GLP-1 class is the most competitive on our site. It does not mean any product is safe to use. Everything here is research-use-only.
What Onyx actually publishes
The reason Onyx earns a high transparency grade is the per-batch Certificate of Analysis. For products in their catalog, Onyx publishes a COA tied to a specific batch. We link these from each product page and from our lab-data page so you can read them yourself rather than take our word for it.
The COAs are run by a third-party lab (Kovera Labs appears on the certificates), and each one lists a batch code, the compound, and an HPLC purity figure. That batch code is the important part: it is what lets you match the certificate to the actual vial. Here is a representative sample of real per-batch purities from the COAs we link.
| Compound | Purity | Batch |
|---|---|---|
| GHK-Cu | 99.978% | GHK0925-100-1 |
| KPV | 99.957% | KPV0126-10-1 |
| Ipamorelin | 99.938% | IPA-2026-0320 |
| Semax | 99.942% | SEM-2026-0320 |
| BPC-157 | 99.816% | BPC0925-5-1 |
| Tirzepatide | 99.223% | Tirzepatide |
| NAD+ | 99.272% | NAD+ |
| Retatrutide | 98.771% | Retatrutide |
A few honest notes on reading this table. The smaller peptides (GHK-Cu, KPV, Semax, Ipamorelin) sit very high, around 99.9%. The larger and more complex GLP-1 class molecules (tirzepatide, retatrutide) come in a little lower, in the high 98% to low 99% range. That pattern is normal for these compounds and is not a red flag on its own. What matters is that Onyx puts the numbers in front of you per batch instead of asking you to trust a single marketing claim.
How their pricing stacks up
Transparency is one half of the story. Price is the other, and this is where Onyx stands out on our site. Across the vendors we track, Onyx currently has the cheapest GLP-1 class options.
- Tirzepatide: $94.99 for 30 mg, which works out to $3.17/mg. That is the cheapest tirzepatide on our site.
- Semaglutide: $74.99 for 15 mg, or $5/mg. Also the cheapest semaglutide we track.
- Retatrutide: $92.99 for 10 mg ($9.3/mg).
- Ipamorelin: $90 for 10 mg ($9/mg).
- IGF-1 LR3: $79.99 for 1 mg.
If you are price-shopping the GLP-1 class specifically, Onyx is the value leader on our site right now, and they pair that price with a published COA. You can see the full per-milligram breakdown on our tirzepatide page and semaglutide page, and compare the rest of the field with our side-by-side tool. Retatrutide buyers can check the current field on our retatrutide page.
What to watch and how to verify your own batch
Here is the part a balanced review has to say out loud. The purity numbers above are strong, but you should understand exactly what they are and are not before you trust them.
- We do not run the labs ourselves. The purity is read off Onyx's published certificate, produced by a third-party lab. We link it; we do not test it.
- Match the batch code before you trust a number. Always confirm the batch code printed on the vial you actually receive matches the batch on the COA. A certificate for a different batch tells you nothing about the vial in your hand.
- Purity is about identity, not safety. A high HPLC figure confirms the compound is what it says it is and is largely free of impurities. It says nothing about whether any compound is safe for any use. This is research-use-only product.
- The GLP-1 numbers are lower than the small peptides. That is expected, but if a lower figure matters to you, read the actual certificate rather than relying on a catalog headline.
Frequently asked.
Is Onyx Biolabs legit?
On the measure we can verify, published per-batch lab data, yes. We grade Onyx Biolabs Grade A (Established) and track 20 of their products. They publish per-batch COAs run by a third-party lab, and their pricing on the GLP-1 class is the most competitive on our site. That is a transparency grade, not a safety endorsement: everything is research-use-only.
Who tests Onyx Biolabs peptides?
The COAs are produced by a third-party lab; Kovera Labs appears on the certificates we link. Each certificate lists the batch code, the compound, and an HPLC purity figure. We do not run the testing ourselves, we link the published certificates so you can read them.
Is Onyx Biolabs cheap?
For the GLP-1 class, yes. Onyx currently has the cheapest tirzepatide on our site at $94.99 / 30 mg ($3.17/mg) and the cheapest semaglutide at $74.99 / 15 mg ($5/mg). Retatrutide runs $92.99 / 10 mg and IGF-1 LR3 is $79.99 / 1 mg.
What does Onyx Biolabs sell?
Research peptides. We track 20 of their products, including tirzepatide, semaglutide, retatrutide, ipamorelin, BPC-157, GHK-Cu, KPV, Semax, Selank, IGF-1 LR3, NAD+ and more. Note that Clearly Peptides does not sell anything; we compare prices and lab data and link out to vendors like Onyx.
Does Onyx provide COAs?
Yes. Onyx publishes a per-batch Certificate of Analysis for products, with a batch code, the compound, and an HPLC purity figure. We link these from each product page and from our lab-data page. Always match the batch code on your vial to the certificate before trusting a purity number.