Peptix USA vs S1Research
Two top US peptide sources scored on the identical published formula: lab credibility, shipping, pricing, operating history, and transparency.
- Peptix USA
- 8.15/10
Peptix USA
- S1Research
- 7.75/10
S1Research
Affiliate links: we may earn a commission if you buy. It never changes a score or rank.
Factor by factor
- 8.7Lab Credibilityweight 55%8.7
- 9.0Shipping & Refundweight 20%6.0
- 8.8Pricingweight 15%9.5
- 1.3Operating Historyweight 5%1.8
- 3.5Transparencyweight 5%5.0
- 5Certificates confirmed at the lab29
- 2Labs named on certificates2
Show as a table
| Category | Peptix USA | S1Research |
|---|---|---|
| Lab Credibility | 8.7 | 8.7 |
| Shipping & Refund | 9.0 | 6.0 |
| Pricing | 8.8 | 9.5 |
| Operating History | 1.3 | 1.8 |
| Transparency | 3.5 | 5.0 |
| Overall | 8.15 | 7.75 |
Products both carry, price for price
| Peptide | Peptix USAper unit | S1Researchper unit |
|---|---|---|
| BPC-157Guide → | $4.00/mg | $2.00/mg |
| GLOW | $1.21/mg | $0.60/mg |
| RetatrutideGuide → | $5.90/mg | $1.50/mg |
| Tesamorelin | $6.20/mg | $2.35/mg |
| TirzepatideGuide → | $2.90/mg | $1.00/mg |
How they compare: the verdict
Peptix USA takes this matchup by a razor-thin margin, 8.15 to 7.75 on the published formula. Its biggest edge is shipping & refunds, where it scores 9.0 against S1Research's 6.0.
It isn't a clean sweep. S1Research actually edges ahead on transparency (5.0 vs 3.5), so if that factor matters most to you it's worth weighing.
On lab evidence, the heaviest-weighted factor, both Peptix USA and S1Research have independently verified third-party COAs, so the gap comes down to the other categories.
Across the 5 peptides both carry, S1Research is cheaper per unit more often (Peptix USA wins on 0, S1Research on 5). The price-for-price table below has the detail, per mg (or per IU or mL for products sold that way).
Affiliate links: we may earn a commission if you buy. It never changes a score or rank.
Peptix USA vs S1Research: FAQ
Peptix USA or S1Research: which is better?
Peptix USA takes this matchup by a razor-thin margin, 8.15 to 7.75 on the published formula. Its biggest edge is shipping & refunds, where it scores 9.0 against S1Research's 6.0. It isn't a clean sweep. S1Research actually edges ahead on transparency (5.0 vs 3.5), so if that factor matters most to you it's worth weighing. On lab evidence, the heaviest-weighted factor, both Peptix USA and S1Research have independently verified third-party COAs, so the gap comes down to the other categories. Across the 5 peptides both carry, S1Research is cheaper per unit more often (Peptix USA wins on 0, S1Research on 5). The price-for-price table below has the detail, per mg (or per IU or mL for products sold that way).
Do Peptix USA and S1Research both use third-party testing?
Peptix USA: independently verified third-party COAs. S1Research: independently verified third-party COAs.
How was this comparison scored?
Both vendors are scored on the identical published formula: lab credibility 55%, shipping 20%, pricing 15%, operating history 5%, transparency 5%. When third-party testing cannot be independently verified, a testing gate holds the score under a cap that starts at 6.0 and rises by at most 2.5 points for operating history, shipping and reviews. Neither vendor can pay to change a score.
More comparisons
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