mcg to IU Converter

Convert between micrograms (mcg) and International Units (IU) for common vitamins and hormone substances.

Choose a substance and convert between mass in micrograms (mcg) and biological activity in International Units (IU).

The calculator works both ways: edit mcg to solve IU, or edit IU to solve mcg.

Includes common conversion factors for vitamin A forms, vitamin D, vitamin E forms, and insulin analogs.

Substance

Weight (mass)

International units (IU)

Conversion factor for this substance: 40 IU per mcg

Conversion result

25 mcg = 1000 IU