Enter the insulin mass in milligrams and select an insulin preparation to determine the approximate number of insulin units (IU) using the standard potency relationship.

mg to Insulin Units Converter

Enter the insulin mass in mg to calculate the approximate insulin units

Standard reference relationship: 1 IU ≈ 0.0347 mg of human insulin activity.

mg to Insulin Units Formula

The following formula is used to calculate insulin units from a known insulin mass in milligrams.

IU = mg / 0.0347

Reverse formula:

mg = IU × 0.0347

Variables:

  • IU is the approximate number of insulin units
  • mg is the insulin mass in milligrams
  • 0.0347 is the approximate milligrams of insulin per international unit

To calculate insulin units from mg, divide the insulin mass by 0.0347. To convert units back to mg, multiply the number of units by 0.0347.

What is mg to Insulin Units Conversion?

International insulin units express biologic activity, while milligrams describe the physical mass of insulin. Under the standard reference definition for human insulin, 1 IU is approximately equal to 0.0347 mg of pure human insulin activity. This makes it possible to translate a measured insulin mass into an approximate unit count.

Because the relationship is linear, the unit count increases in direct proportion to the mass. For example, 0.347 mg corresponds to about 10 IU, and 3.47 mg corresponds to about 100 IU.

In clinical settings, insulin is usually prescribed directly in units and supplied by concentration, such as U-100, which means 100 units per milliliter. The mg-to-IU relationship is most useful in pharmacology, formulation, and research contexts where insulin mass is specified.

How to Convert mg to Insulin Units?

The following steps outline how to convert a known insulin mass in mg to insulin units.

  1. First, determine the mass of insulin in milligrams (mg).
  2. Next, use the standard insulin reference relationship of 1 IU ≈ 0.0347 mg.
  3. Then divide the insulin mass by 0.0347 using the formula IU = mg / 0.0347.
  4. Finally, review the result and compare it with the calculator above.

mg to Insulin Units Conversion Table

The table below applies the formula IU = mg / 0.0347 to several common insulin masses. Values are rounded to two decimal places where needed.

Insulin Mass Approximate Units (IU)
0.0347 mg 1 IU
0.0694 mg 2 IU
0.347 mg 10 IU
3.47 mg 100 IU
34.7 mg 1000 IU
50 mg 1440.92 IU

This table is based on the standard human insulin definition and should be interpreted as an approximate reference conversion. Product labeling and dosing are typically expressed directly in units rather than milligrams.

Example Problem:

Use the following variables as an example problem to test your knowledge.

Insulin Mass (mg) = 10

Insulin Units (IU) = 10 / 0.0347 = 288.18