Price per milligram: how to compare vial strengths properly
Written 23 September 2026 by the trade desk. About 2 minutes to read.
Two boxes of the same compound can look nothing alike on price and still be the same deal. The number that makes them comparable is the price per milligram, and it takes one division to get.
The arithmetic
Box price, divided by vials in the box, divided by milligrams in a vial. A box of ten 10 mg vials at $40 is $4.00 a vial and $0.40 per mg. A box of ten 30 mg vials at $90 is $9.00 a vial and $0.30 per mg. The second box costs more and is the better price. Every line on this site prints all three figures so nobody has to do this on a phone.
Why bigger vials cost less per milligram
Most of the cost of a vial is not the peptide. It is the vial, the stopper, the seal, the fill, the freeze-drying, the label, the testing and the handling, and those cost about the same whether the vial holds 5 mg or 50 mg. Spread over more milligrams, the fixed part shrinks. Across our retatrutide range the per-milligram price falls steadily from the 5 mg vial to the 100 mg vial, which is exactly this effect.
When the cheapest per milligram is the wrong buy
When the vial is larger than the amount you will use from one vial. A reconstituted vial does not keep the way a sealed one does, so a laboratory that works in small amounts can waste more in a large vial than it saves on price. Match the vial to the size of the work, then compare per milligram within that size.
Comparing across suppliers
Compare per milligram, at the same purity limit, with freight included on both sides. A list price that excludes freight, or a purity of 95 percent set against one of 98, is not a like-for-like figure. Our prices include freight and every line is released at not less than 98 percent.
Strength is not the only unit
Some lines are measured in international units rather than milligrams, and the solution lines are stated by total active content in a 10 mL vial. The per-unit figure on those pages is per IU or per mL, and the same division applies.
Applies to
Retatrutide, Tirzepatide, among others. Every compound.
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