Mentzer Index Calculator
Calculate the Mentzer Index from MCV and red blood cell count.
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Mentzer Index
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Screening index only; no anemia cause is assigned
MCV: — fL · RBC: — million/µL
About
The Mentzer Index divides mean corpuscular volume by red blood cell count. It was introduced as a screening index in microcytic anemia, but its performance varies across populations and overlapping conditions. This page reports the arithmetic without assigning an anemia cause.
Formula
Interpretation
Input units: MCV is entered in femtoliters. RBC count may be labeled million/µL or 10¹²/L; these formats have the same numeric value.
Worked example: MCV 72 fL and RBC 5.5 million/µL gives 72 ÷ 5.5 = 13.1.
Applicable population: A screening calculation studied mainly in people with microcytosis. A commonly cited dividing value near 13 is method- and population-dependent and is not applied as an automatic label here.
Limitations: Iron deficiency and thalassemia trait can coexist, and other causes of microcytosis are not represented. Ferritin, iron studies, hemoglobin analysis, CBC findings, age, ancestry, pregnancy, and clinical context may be needed.
FAQ
Disclaimer
Educational and informational reference only. Not intended to replace professional medical advice, diagnosis, treatment, or independent verification.