Is it cheaper to buy peptides in bulk vials?

Generally yes, per milligram. Across the sellers this site tracks, a larger vial almost always prices out lower per milligram than a small one of the same compound, because packaging, shipping, and testing costs are spread over more product. That is a statement about unit economics, not a recommendation to buy more of any compound than you need, and it does not account for a molecule's roughly 28 day stability window once it is reconstituted.

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 buying, vendors, and lab testing. How to evaluate a seller's claims, certificates of analysis, and pricing.