HCG Reconstitution & Dosage Calculator: 5,000 IU & 10,000 IU Vials

How the HCG dosage calculation works

Every HCG dosage calculator runs the same three steps. Doing them by hand takes about ten seconds once you have seen it.

1. Concentration. Vial IU divided by BAC water mL. A 5,000 IU vial with 2 mL of bacteriostatic water is 5000 / 2 = 2,500 IU/mL.
2. Draw volume. Target dose divided by concentration. For 250 IU: 250 / 2500 = 0.1 mL.
3. Syringe units. Draw volume multiplied by 100 on a U-100 insulin syringe. 0.1 mL becomes the 10 unit line.

The unit line is where mixing ratio matters most. The same 250 IU dose is 10 units at 2,500 IU/mL, 5 units at 5,000 IU/mL, and 12.5 units at 2,000 IU/mL. Nothing about the dose changed; only the water did. That is why a calculator that asks for vial size and water volume separately gives a different answer than a chart that assumes one ratio.

Converting HCG IU to insulin syringe units

HCG is measured in international units, syringes are marked in units of volume, and the two are not the same thing. A 100 unit insulin syringe holds 1 mL, so each mark is 0.01 mL. Multiply your draw volume in mL by 100 and you have the mark to fill to.

Worked in reverse: if you are told to draw to the 20 unit line from a 2,500 IU/mL mix, that is 0.2 mL, which is 500 IU. Reading a chart from someone else's mixing ratio is the single most common way a dose ends up double or half of what was intended.

How long a vial lasts

Vial life is dose driven, not water driven. Adding more bacteriostatic water spreads the same total IU over a larger volume; it does not create more doses.

A 5,000 IU vial gives 40 doses at 125 IU, 20 at 250 IU, or 10 at 500 IU. At 250 IU every other day that is roughly 40 days. A 10,000 IU vial doubles each of those. Reconstituted HCG is generally kept at 2 to 8 degrees C and used within 30 days, so a large vial mixed all at once can outlive its own shelf life before the doses run out.