International units to syringe units
IU Calculator
For products labelled in international units (IU) instead of mg. Enter the IU in the vial, the water added and the dose in IU.
IU reconstitution calculator
Example values are loaded. Replace them with the numbers on your own vial.
IU and syringe units are different things
An international unit (IU) measures biological activity, and its size is defined separately for each substance. A syringe unit is a volume: 0.01 mL on a U-100 syringe. They share the word "unit" and nothing else, which is why a separate calculator helps.
Draw (mL) = dose (IU) ÷ concentration
Syringe units = mL × 100
Example: a 5,000 IU vial with 5 mL of water is 1,000 IU/mL. A 500 IU dose is 0.5 mL, or 50 units.
Somatropin: mg and IU
Somatropin (recombinant human growth hormone) is often labelled in mg in some markets and IU in others. The accepted conversion is 1 mg = 3 IU. Choose "mg somatropin" above and the calculator converts the vial to IU first. This conversion is specific to somatropin; it does not apply to other substances.
Substance-specific pages: HCG calculator and HGH calculator.
Frequently asked questions
How many IU are in 1 mg of HGH?
For somatropin, 1 mg equals 3 IU. A 12 mg cartridge holds 36 IU.
Is an IU the same as a unit on the syringe?
No. IU measures biological activity. A syringe unit is a volume, 0.01 mL on a U-100 syringe. The calculator converts one into the other using the vial's concentration.