Head-to-head · 2026 audit

Peptix USA vs Southern Aminos

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

Southern Aminos
8.09/10

Southern Aminos

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Higher score · 0.06 ahead

Peptix USA

8.15 /10

StrongShop Peptix USA → (opens in new tab)

 

Southern Aminos

8.09 /10

Strong

Factor by factor

Peptix USAFactorSouthern Aminos
  • 8.7Lab Credibilityweight 55%9.0
  • 9.0Shipping & Refundweight 20%7.5
  • 8.8Pricingweight 15%8.5
  • 1.3Operating Historyweight 5%2.3
  • 3.5Transparencyweight 5%5.0
  • 5Certificates confirmed at the lab28
  • 2Labs named on certificates2
Show as a table
Peptix USA vs Southern Aminos score breakdown by category
CategoryPeptix USASouthern Aminos
Lab Credibility8.79.0
Shipping & Refund9.07.5
Pricing8.88.5
Operating History1.32.3
Transparency3.55.0
Overall8.158.09

Products both carry, price for price

Price per unit (mg unless marked) for products both Peptix USA and Southern Aminos carry
PeptidePeptix USAper unitSouthern Aminosper unit
BPC-157Guide →$4.00/mg$3.84/mg
GLOW$1.21/mg$1.13/mg
RetatrutideGuide →$5.90/mg$1.84/mg
Tesamorelin$6.20/mg$3.96/mg
TirzepatideGuide →$2.90/mg$2.07/mg

How they compare: the verdict

Peptix USA takes this matchup by a razor-thin margin, 8.15 to 8.09 on the published formula. Its biggest edge is shipping & refunds, where it scores 9.0 against Southern Aminos's 7.5.

It isn't a clean sweep. Southern Aminos 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 Southern Aminos have independently verified third-party COAs, so the gap comes down to the other categories.

Across the 5 peptides both carry, Southern Aminos is cheaper per unit more often (Peptix USA wins on 0, Southern Aminos 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 Southern Aminos: FAQ

Peptix USA or Southern Aminos: which is better?

Peptix USA takes this matchup by a razor-thin margin, 8.15 to 8.09 on the published formula. Its biggest edge is shipping & refunds, where it scores 9.0 against Southern Aminos's 7.5. It isn't a clean sweep. Southern Aminos 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 Southern Aminos have independently verified third-party COAs, so the gap comes down to the other categories. Across the 5 peptides both carry, Southern Aminos is cheaper per unit more often (Peptix USA wins on 0, Southern Aminos 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 Southern Aminos both use third-party testing?

Peptix USA: independently verified third-party COAs. Southern Aminos: 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

Other head-to-heads featuring Peptix USA or Southern Aminos.

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