Independent side-by-side comparison of Mei Peptide and Penguin Peptides — third-party lab grades, tested purity, COA availability, FDA warnings, and community ratings.
Bottom line: Penguin Peptides has more published third-party tests (18 vs 8).
Every figure below is either measured by an independent laboratory or read from the vendor's own website, and the source is named against it. PeptideAtlas is not affiliated with either vendor.
Mei Peptide: 8 independent Janoshik assays, across 8 substances, median measured purity 99.1%, most recent 2025-11-20. Penguin Peptides: 18 independent Janoshik assays, across 17 substances, median measured purity 99.8%, most recent 2026-01-22.
| Attribute | Mei Peptide | Penguin Peptides |
|---|---|---|
| Third-party tests | 8 tests, avg purity 99.2% | 18 tests, avg purity 99.2% |
| COA available | No | No |
| Endotoxin tested | No | No |
| FDA warnings | None on record | None on record |
| Substance | Mei Peptide | Penguin Peptides |
|---|---|---|
| GLOW 70mg | Not tested | purity not reported (2 assays, latest 2026-01-21) |
| KLOW (ghk Or Ghk-cu/ Tb-500/ Bpc-157/ Kpv) | purity not reported (1 assay, latest 2025-11-20) | Not tested |
| Sermorelin | 99.01% (1 assay, latest 2025-11-19) | Not tested |
| Cjc-1295 With DAC 5 | 98.28% (1 assay, latest 2025-11-19) | Not tested |
| Tirzepatide 30mg | 99.78% (1 assay, latest 2025-07-22) | Not tested |
| Tesamorelin 10mg | 99.08% (1 assay, latest 2025-07-19) | Not tested |
| Retatrutide 10mg | 99.66% (1 assay, latest 2025-07-19) | Not tested |
| Nad+500 | purity not reported (1 assay, latest 2025-07-18) | Not tested |
| Bpc5mg+tb5mg Blend | purity not reported (1 assay, latest 2025-07-18) | Not tested |
| HGH 191AA 36iu | Not tested | 96.33% (1 assay, latest 2026-01-22) |
| Glp-1 T 120mg | Not tested | 99.88% (1 assay, latest 2026-01-21) |
| Glp-1 T 60mg | Not tested | 99.86% (1 assay, latest 2026-01-21) |
Penguin Peptides. Mei Peptide: 8 independent Janoshik assays, across 8 substances, median measured purity 99.1%, most recent 2025-11-20. Penguin Peptides: 18 independent Janoshik assays, across 17 substances, median measured purity 99.8%, most recent 2026-01-22. These are third-party Janoshik assays published against the vendor, not the vendor's own certificates.
Full profiles: Mei Peptide, Penguin Peptides.
Full lab-test records: All 8 Mei Peptide lab tests, All 18 Penguin Peptides lab tests.
Related comparisons: Mei Peptide vs Ameano Peptides, Penguin Peptides vs Apex Peptides, Mei Peptide vs Certified Peptides, Penguin Peptides vs Certified Peptides, Mei Peptide vs Cocer Peptides, Penguin Peptides vs Fenrir Labs Uk LTD.