We Independently Tested 20 Peptide Samples. Here’s What We Found.
Six months, three laboratories, and 20 anonymously purchased samples from 12 companies. Purity ranged from 61% to 99.2% — and two products failed verification entirely.
Special ReportNextGen Peptides
Large catalog and competitive pricing; recent testing showed one under-label quantity result.
Best Value
This company is under active review. See the testing history below.
Tests2
Score updatedAug 2, 2026
Methodologyv2.3
Movement -3down 3 points
Score Breakdown
Seven weighted dimensions, methodology v2.3. How weights work →
- Testing & Quality 25% 78
- Transparency 18% 80
- Manufacturing & Sourcing 15% 82
- Customer Experience 12% 86
- Shipping & Fulfillment 12% 90
- Policies & Returns 8% 84
- Community Feedback 10% 84
Score History
Historical Index Score™ snapshots. Scores are versioned and never overwritten.
Editorial Assessment
NextGen Peptides offers one of the widest catalogs and most aggressive pricing in the category. Purity results have been acceptable, but our May 2026 quantity test measured 8.9mg in a product labeled 10mg — a 11% shortfall the company attributes to fill variance. We have flagged the product line for retesting next cycle.
- Shipping & fulfillment
- Fastest average delivery in our 2026 fulfillment testing (2.1 days).
- Policies & returns
- 30-day policy; straightforward in our experience test.
- Testing record
- 5 independent tests. One quantity discrepancy under review.
Independent Testing History
Testing databaseRelated Reporting
Community testing patterns: what 400 user reports tell us about fulfillment
Aggregated consumer reports show delivery times improving — and two companies driving most complaints.
CommunityCold-chain shipping study: temperature logging across 12 suppliers
We shipped temperature loggers with orders from every indexed company. Summer transit told a clear story.
Lab InsightsCommunity Discussions
Forum 16 replies