Enter the Red Blood Cell count, Hematocrit, and Mean Corpuscular Volume into the calculator to determine the Retic Index. This calculator can also evaluate any of the variables given the others are known.

Retic Index Formula

The following formula is used to calculate the Retic Index.

RI = (RBC * HCT * MCV) / 100


  • RI is the Retic Index RBC is the Red Blood Cell count HCT is the Hematocrit MCV is the Mean Corpuscular Volume

To calculate the Retic Index, multiply the Red Blood Cell count by the Hematocrit, then multiply the result by the Mean Corpuscular Volume. Divide the final result by 100.

What is a Retic Index?

A Retic Index, or Reticulocyte Index, is a medical measurement used to evaluate the rate at which new red blood cells (reticulocytes) are produced and released by the bone marrow. This index is often used in diagnosing and monitoring conditions such as anemia or bone marrow disorders. A high Retic Index indicates an increased production of red blood cells, while a low index may suggest a decreased production.

How to Calculate Retic Index?

The following steps outline how to calculate the Retic Index:

  1. First, determine the value of RBC (Red Blood Cell count).
  2. Next, determine the value of HCT (Hematocrit).
  3. Next, determine the value of MCV (Mean Corpuscular Volume).
  4. Next, gather the formula from above = RI = (RBC * HCT * MCV) / 100.
  5. Finally, calculate the Retic Index.
  6. After inserting the variables and calculating the result, check your answer with the calculator above.

Example Problem:

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

RBC (Red Blood Cell count) = 4.5

HCT (Hematocrit) = 42

MCV (Mean Corpuscular Volume) = 90