Cost per dose calculator

Vials are priced per vial, but you spend per dose. Put your numbers in and see what each one actually costs, how long a vial lasts you, and what you are really spending each month.

$1.13per dose
40doses per vial
5.7weeks per vial
$34per month

$1.61per dose you actually use
28usable doses
12left when it expires
$14binned per vial

Pure arithmetic on the numbers you enter — nothing is recommended or stored, and nothing is sent anywhere. Real-world doses per vial can be slightly lower because a little liquid always stays behind in the vial and needle.

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How cost per dose is worked out

Three steps, no mystery:

The expiry maths most people skip

Doses per vial only counts if you get to them. Once a vial is mixed it has a limited window — commonly quoted as around 28 days refrigerated, though it varies by compound and by what your supplier says. Any doses still sitting in the vial when that window closes were paid for and never used, so your real cost is the vial price divided by the doses you actually reach.

That is why the small vial sometimes wins. A 5 mg vial you finish beats a 10 mg vial you abandon a quarter of the way from the end, even though the bigger one looks cheaper per mg. Matching vial size to your dose and frequency is usually worth more than shopping for a better price per mg.

Why it is worth knowing

A cheaper vial is not always cheaper per dose. A $45 vial holding 10 mg costs less per dose than a $30 vial holding 5 mg, even though the sticker price is higher. Cost per dose is the only number that lets you compare fairly — and it is the number that tells you what a month actually costs before you commit to it.

Track it without the spreadsheet

Peptide Wizard keeps a running cost per dose for every vial you log, so you can see your real monthly spend, compare what you are paying across suppliers, and know how many doses are left before you run out. It also logs your injection sites, warns you when you are reusing one too soon, and reminds you when a dose is due.