STACK
CALCULATOR

For each peptide you add, we multiply your per-injection dose by your injections-per-week and protocol length to get the total milligrams required. Then — and this is the part competitors can't do — we search the actual in-stock SKUs across every tracked vendor and pick the combination that minimizes total cost for exactly that quantity.

Vial sizes matter. A vendor selling 10 mg vials at $80 beats one selling 5 mg vials at $50 on $/mg — but if you only need 6 mg, you'd still buy a 10 mg vial from the first vendor or a 5 mg vial from the second (one vial vs two). The calculator accounts for that by trying every SKU as a candidate and picking the cheapest total, not the lowest $/mg.

We only include in-stock listings — prices you can actually transact at today, not SKUs that are out of stock. Prices refresh daily from each vendor's live catalog. When two vendors tie on cost, we break the tie toward the fewer-vials option, then toward the smaller surplus, then toward the higher Stacked Score.