How do you compare insulin units and micrograms?

Insulin units and micrograms are two different ways of measuring the amount of insulin in a preparation. One international unit (IU) of insulin is equivalent to 33.3 micrograms (µg) of pure crystallized insulin.

To convert from insulin units to micrograms, multiply the number of insulin units by 33.3.

For example, 5 IU of insulin is equivalent to 5 × 33.3 = 166.5 µg of insulin.