Where we buy the vial, and what that vendor isn't.

ZestyRat Research

We order from ZestyRat Research. Not because they're the biggest name — they aren't — but because across every order placed through our sites, nothing has gone wrong: no missing packages, no broken seals, no vial that turned up different from the last one. In a category where none of that is guaranteed, boring consistency is the product. Their certificates of analysis are batch-specific, the vials are induction-sealed, shipping is tracked, and they carry most of what this calculator lists — the GLP-1s, BPC-157, TB-500, GHK-Cu, NAD+, the secretagogues, MOTS-c.

Reader code SHAUN10 takes 10% off. It's an affiliate code: we earn a commission, you pay the same or less, and it changes nothing about the math on this site.

What they are not

They are not a clinic. Nobody there will ask what else you're taking, look at your labs, or tell you to slow down. That is the trade you make for a research-grade price, and you should make it with your eyes open. If you want oversight, pay for oversight — a telehealth peptide protocol typically runs $250–600 a month before labs, and that money buys a prescriber. A vial buys a vial.

What to buy for the calculator

• The vial size that makes your dose a clean number. The calculator tells you: a 10 mg tirzepatide vial in 2 mL puts common microdoses at 10, 20, 25 and 50 units.
• Bacteriostatic water, not sterile water — the benzyl alcohol is what lets a reconstituted vial be used over days or weeks.
• U-100 insulin syringes in the size the calculator suggests. 0.3 mL for small doses, 1 mL for anything over 50 units.
• Alcohol swabs.

Vendors we don't earn from

We're asked why we don't list ten vendors. Because we can't personally vouch for ten. The sister sites in this network — Peptides Uncaged, Vial Prices, the Peptide Deal Board — publish price-per-milligram comparisons across many vendors including ones we earn nothing from. Use them to check us.