Enter a value in uIU/mL and select the hormone test to convert the result to IU/mL. This conversion uses the micro prefix, so 1 uIU/mL = 0.000001 IU/mL.

uIU/mL to IU/mL Converter

Enter a value in uIU/mL to calculate the equivalent IU/mL value

Quick Overview: uIU/mL to IU/mL

uIU/mL means micro-international units per milliliter, while IU/mL is international units per milliliter.

The relationship is:

  • 1 IU/mL = 1,000,000 uIU/mL
  • 1 uIU/mL = 0.000001 IU/mL
  • IU/mL = uIU/mL ÷ 1,000,000

This same power-of-ten conversion applies to common hormone tests such as TSH, LH, FSH, hCG, prolactin, and insulin.

uIU/mL to IU/mL Formula

The following formula is used to convert micro-international units per milliliter to international units per milliliter.

IU/mL = uIU/mL / 1,000,000

Variables:

  • IU/mL is the value in international units per milliliter
  • uIU/mL is the value in micro-international units per milliliter
  • 1,000,000 is the conversion factor between micro-units and base units

To calculate IU/mL, divide the value in uIU/mL by 1,000,000.

What is uIU/mL to IU/mL?

uIU/mL stands for micro-international units per milliliter, and IU/mL stands for international units per milliliter. Since the prefix micro means one-millionth, 1 uIU/mL is equal to 0.000001 IU/mL. This means converting from uIU/mL to IU/mL is a simple power-of-ten unit conversion and does not depend on the specific hormone selected. Tests such as TSH, LH, FSH, hCG, prolactin, and insulin all use the same numerical conversion between these two units.

How to Calculate uIU/mL to IU/mL?

The following steps outline how to convert uIU/mL to IU/mL.


  1. First, determine the lab value in uIU/mL.
  2. Next, identify the unit relationship: 1 IU/mL = 1,000,000 uIU/mL.
  3. Divide the uIU/mL value by 1,000,000 to convert it to IU/mL.
  4. After calculating the result, check your answer with the converter above.

uIU/mL to IU/mL Conversion Table

The table below shows example conversions for several common hormone tests using the formula IU/mL = uIU/mL ÷ 1,000,000.

Test / Analyte Example Value (uIU/mL) Value in IU/mL
TSH 2,500 uIU/mL 0.0025 IU/mL
LH 1,500 uIU/mL 0.0015 IU/mL
FSH 1,000 uIU/mL 0.001 IU/mL
hCG 10,000 uIU/mL 0.01 IU/mL
Prolactin 500 uIU/mL 0.0005 IU/mL
Insulin 200 uIU/mL 0.0002 IU/mL

Laboratories may report endocrine lab results in either uIU/mL or IU/mL depending on the reporting system and reference standards used. Because the only difference is the micro prefix, the conversion is straightforward and can be used to compare values across references, reports, and calculators.

Example Problem:

Use the following example to test your knowledge.

Value = 2,500 uIU/mL

Formula: IU/mL = uIU/mL ÷ 1,000,000

Result = 2,500 ÷ 1,000,000 = 0.0025 IU/mL