Independent side-by-side comparison of Maximum Peps and Peptide Gurus — third-party lab grades, tested purity, COA availability, FDA warnings, and community ratings.
Bottom line: Peptide Gurus holds the stronger independent lab grade (ungraded vs D); Maximum Peps shows higher average tested purity (99.7% vs 99.5%); Peptide Gurus has more published third-party tests (63 vs 1).
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.
Maximum Peps: 1 independent Janoshik assay, median measured purity 99.7%, most recent 2026-01-28. Peptide Gurus: 63 independent Janoshik assays, across 58 substances, median measured purity 99.7%, most recent 2026-04-24.
| Attribute | Maximum Peps | Peptide Gurus |
|---|---|---|
| Independent lab grade | Not graded | D |
| Third-party tests | 1 test, avg purity 99.7% | 63 tests, avg purity 99.5% |
| COA available | No | No |
| Endotoxin tested | No | No |
| FDA warnings | None on record | None on record |
| Substance | Maximum Peps | Peptide Gurus |
|---|---|---|
| Retatrutide 10mg | Not tested | 99.51% (3 assays, latest 2026-04-14) |
| Tirzepatide 30mg | Not tested | 99.84% (3 assays, latest 2026-04-14) |
| Tirzepatide 10mg | Not tested | 99.79% (2 assays, latest 2026-04-14) |
| Glp-3rt 20mg | 99.71% (1 assay, latest 2026-01-28) | Not tested |
| Ss-31 40mg | Not tested | 99.73% (1 assay, latest 2026-04-24) |
| Wolverine(bpc-157 5mg Blend With Tb-500 5mg) | Not tested | purity not reported (1 assay, latest 2026-04-23) |
| Wolverine(bpc-157 10mg Blend With Tb-500 10mg) | Not tested | purity not reported (1 assay, latest 2026-04-23) |
| Pinealon 20mg | Not tested | 99.17% (1 assay, latest 2026-04-14) |
| Oxytocin 10mg | Not tested | 97.53% (1 assay, latest 2026-04-14) |
| Hcg 10,000 IU | Not tested | purity not reported (1 assay, latest 2026-04-14) |
| Pt-141 10mg | Not tested | 99.90% (1 assay, latest 2026-04-14) |
| Tesamorelin 10mg | Not tested | 99.74% (1 assay, latest 2026-04-14) |
| Checked | Maximum Peps | Peptide Gurus |
|---|---|---|
| Certificates of analysis | None found on the site | Not stated |
| Products listed | 67 | Not stated |
| Public pricing | Listed on the site | Not stated |
| Research-use-only notice | Published | Not stated |
Peptide Gurus. Maximum Peps: 1 independent Janoshik assay, median measured purity 99.7%, most recent 2026-01-28. Peptide Gurus: 63 independent Janoshik assays, across 58 substances, median measured purity 99.7%, most recent 2026-04-24. These are third-party Janoshik assays published against the vendor, not the vendor's own certificates.
We found no certificates of analysis anywhere on Maximum Peps' site, and we have not read Peptide Gurus' site. A published COA is the vendor's own document; the assay figures elsewhere on this page are independent of it.
Full profiles: Maximum Peps, Peptide Gurus.
Full lab-test records: All 1 Maximum Peps lab test, All 63 Peptide Gurus lab tests.
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