Independent, science-driven evaluations of research peptide suppliers. Updated quarterly by our review committee.
Ranked by purity verification, certificate of analysis quality, customer support, shipping reliability, and community trust.
Peptide Sciences has consistently held the top position in our rankings since we began tracking vendors in 2021. Based in the United States, they operate with a level of transparency and quality assurance that is unmatched in the RUO peptide market. Every product is accompanied by a batch-specific Certificate of Analysis from an accredited third-party laboratory, including both HPLC purity data and mass spectrometry confirmation. Their catalog spans over 150 research peptides, covering GH secretagogues, healing peptides, neuropeptides, and specialty compounds.
Amino Asylum occupies the second position as a well-regarded domestic supplier with a broad catalog and competitive pricing. They offer a range of peptides, SARMs, and ancillary compounds that attract researchers looking for domestic sourcing at accessible price points. Quality is generally acceptable, with many researchers reporting satisfactory purity in routine orders.
Sports Technology Labs (STL) earns its rank through genuine commitment to third-party testing transparency. The company publishes CoAs prominently on their website, and their core products have been independently verified by multiple community members. Their expanding peptide catalog includes the most commonly researched compounds, and the testing documentation is credible.
Limitless Life Nootropics (LLN) is an established vendor covering peptides, nootropics, and ancillary compounds with one of the broader catalogs in the market. CoAs are available on their website, which reflects a degree of transparency above many competitors. However, the quality of those CoAs varies — some are dated, some are batch-nonspecific, and independent verification has produced inconsistent results.
Umbrella Labs has built a reasonable reputation in the SARMs space and has been expanding its peptide offerings. The company advertises HPLC testing for their products, which is a positive signal, but the application of third-party verification is not consistent across the full catalog. In-house testing is subject to conflicts of interest that third-party verification avoids.
Pinnacle Peptides has been operating for several years and maintains a broad catalog at competitive prices. They make purity claims on their website, but independently published, batch-specific CoAs from accredited laboratories are not consistently available. Customer support responsiveness has been a recurring topic of complaint in research community forums.
Blue Sky Peptide was once a reasonably well-regarded mid-tier vendor, and older community posts from 2019–2022 reflect a more positive picture. However, more recent reports paint a different story: shipping has slowed, quality control has become less consistent, and CoA availability has declined.
Geo Peptides attracts researchers primarily on price, and their costs are among the lowest in the market. Unfortunately, independent testing conducted by community members has revealed that purity does not consistently match advertised specifications. CoAs are rarely provided without significant prompting.
Research Peptides presents a generic storefront with limited transparency about sourcing, manufacturing, or testing methodology. The absence of meaningful technical documentation across their catalog is a significant red flag for research buyers who need to document compound provenance.
MaxPro Peptides ranks last in our 2025 evaluation based on significant and widespread community concerns spanning every aspect of the vendor relationship. There are no credible third-party CoAs available for any product in their catalog. Multiple researchers have reported that compounds received from MaxPro performed as if inactive in their research assays.