Independent side-by-side comparison of HK Peptides and Peptide Sciences — third-party lab grades, tested purity, COA availability, FDA warnings, and community ratings.
Bottom line: HK Peptides has more published third-party tests (5 vs 0); Peptide Sciences carries more community reviews (1247).
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.
HK Peptides: 5 independent Janoshik assays, across 5 substances, median measured purity 99.7%, most recent 2025-11-03. Peptide Sciences has no independent Janoshik assays on file.
| Attribute | HK Peptides | Peptide Sciences |
|---|---|---|
| Independent lab grade | C | C |
| Third-party tests | 5 tests, avg purity 98.7% | None published |
| Community rating | No reviews | 4.7/5 (1247 reviews) |
| COA available | No | Yes |
| Endotoxin tested | No | No |
| FDA warnings | None on record | None on record |
| Year established | Unknown | 1990 |
| Substance | HK Peptides | Peptide Sciences |
|---|---|---|
| HGH 24 IU | 95.42% (1 assay, latest 2025-11-03) | Not tested |
| KPV 10mg | 99.79% (1 assay, latest 2025-04-09) | Not tested |
| Tirzepatide 30mg | 99.70% (1 assay, latest 2024-09-30) | Not tested |
| Tirzepatide 10mg | 99.70% (1 assay, latest 2024-09-30) | Not tested |
| Nad+ 500mg | purity not reported (1 assay, latest 2024-09-26) | Not tested |
| Checked | HK Peptides | Peptide Sciences |
|---|---|---|
| Certificates of analysis | None found on the site | Not stated |
| Products listed | 15 | Not stated |
| Ships to | United States, Europe, Worldwide | Not stated |
| Stated origin | China | Not stated |
HK Peptides. HK Peptides: 5 independent Janoshik assays, across 5 substances, median measured purity 99.7%, most recent 2025-11-03. Peptide Sciences has no independent Janoshik assays on file. These are third-party Janoshik assays published against the vendor, not the vendor's own certificates.
We found no certificates of analysis anywhere on HK Peptides' site, and Peptide Sciences states that COAs are available. A published COA is the vendor's own document; the assay figures elsewhere on this page are independent of it.
HK Peptides states it ships to United States, Europe, Worldwide, and Peptide Sciences does not state one. Both are read from the vendors' own sites.
Full profiles: HK Peptides, Peptide Sciences.
Full lab-test records: All 5 HK Peptides lab tests.
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