Independent side-by-side comparison of Mei Peptide and Modern Peptides — third-party lab grades, tested purity, COA availability, FDA warnings, and community ratings.
Bottom line: Modern Peptides shows higher average tested purity (99.7% vs 99.2%); Modern Peptides has more published third-party tests (25 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. Modern Peptides: 25 independent Janoshik assays, across 20 substances, median measured purity 99.8%, most recent 2026-02-24.
| Attribute | Mei Peptide | Modern Peptides |
|---|---|---|
| Third-party tests | 8 tests, avg purity 99.2% | 25 tests, avg purity 99.7% |
| COA available | No | No |
| Endotoxin tested | No | No |
| FDA warnings | None on record | None on record |
| Substance | Mei Peptide | Modern Peptides |
|---|---|---|
| Tirzepatide 30mg | 99.78% (1 assay, latest 2025-07-22) | 99.85% (1 assay, latest 2026-01-26) |
| Retatrutide 10mg | 99.66% (1 assay, latest 2025-07-19) | 99.74% (2 assays, latest 2026-01-26) |
| Retatrutide 20mg | Not tested | 99.80% (3 assays, latest 2026-02-24) |
| Tirzepatide 15mg | Not tested | 99.78% (2 assays, latest 2026-01-16) |
| Tesamorelin 20mg | Not tested | 99.75% (2 assays, latest 2026-01-09) |
| 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 |
| Tesamorelin 10mg | 99.08% (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 |
| Retatrutide 50mg | Not tested | 99.92% (1 assay, latest 2026-02-24) |
| Checked | Mei Peptide | Modern Peptides |
|---|---|---|
| Certificates of analysis | Not stated | 1 published on the site |
| Products listed | Not stated | 75 |
| Public pricing | Not stated | Listed on the site |
| Payment methods | Not stated | Cryptocurrency, Bank Transfer, Credit Card |
| Ships to | Not stated | United States, United Kingdom, Canada, Worldwide |
| Carriers | Not stated | FedEx, UPS, USPS, Canada Post |
| Research-use-only notice | Not stated | Published |
Modern Peptides. Mei Peptide: 8 independent Janoshik assays, across 8 substances, median measured purity 99.1%, most recent 2025-11-20. Modern Peptides: 25 independent Janoshik assays, across 20 substances, median measured purity 99.8%, most recent 2026-02-24. These are third-party Janoshik assays published against the vendor, not the vendor's own certificates.
Tirzepatide 30mg has been independently assayed for both. Mei Peptide measured a median 99.78% across 1 assay; Modern Peptides measured 99.85% across 1. Purity reflects the lots actually tested, not every batch either vendor sells.
We have not read Mei Peptide's site, and Modern Peptides publishes 1 certificate of analysis on its own site. A published COA is the vendor's own document; the assay figures elsewhere on this page are independent of it.
Mei Peptide does not state a shipping region, and Modern Peptides states it ships to United States, United Kingdom, Canada, Worldwide. Both are read from the vendors' own sites.
Full profiles: Mei Peptide, Modern Peptides.
Full lab-test records: All 8 Mei Peptide lab tests, All 25 Modern Peptides lab tests.
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