Are research peptides legal to buy in the US?

In most cases, yes. Buying and owning a compound labeled research use only is not a crime in itself, because the label says it is sold for lab research, not as a drug for a person. That legal gap is not approval. It just means no regulator has checked the product for use in people. Using it on yourself goes beyond what the label allows.

Legal status by country, one page per compound

Educational use only. This database summarizes published research and is not medical advice. Where a dose appears it is a record of what a trial or clinic ran, or what people describe doing, with its source attached. Nothing here is a recommendation for personal use.

Part of research peptides, the category. What research peptides are, legally and practically, before getting into specific compounds.