MCHC (mean corpuscular hemoglobin concentration) measures how concentrated the hemoglobin is inside your red blood cells — the amount of hemoglobin relative to the size of the cell. Hemoglobin is the protein that lets red blood cells carry oxygen. MCHC is one of the "red blood cell (RBC) indices," a group of measurements calculated as part of a complete blood count (CBC).
MCHC is not usually ordered on its own; it comes automatically as part of a CBC and the red blood cell indices. Doctors most often use these indices together to help find the cause of anemia (a condition with too few healthy red blood cells) and to help tell different types of anemia apart.
MedlinePlus's Medical Encyclopedia lists a general reference range of about 32 to 36 grams per deciliter (g/dL), or 320 to 360 grams per liter (g/L). Reference ranges are general and can vary from lab to lab, and may differ by age, sex, and the testing method used — so the range printed on your own lab report is what applies to your result. A number slightly outside a general range is not, by itself, a diagnosis.
A higher-than-normal MCHC (sometimes described as "hyperchromic") can be seen with more than one condition and does not point to a single cause. General associations noted by MedlinePlus may include hemolytic anemia (red blood cells being broken down faster than the body replaces them), hereditary spherocytosis (a genetic condition affecting red blood cell shape), low folate or vitamin B12 levels, some effects of chemotherapy, or liver disease. This is a general, incomplete list of possible associations — not a diagnosis.
A lower-than-normal MCHC (sometimes described as "hypochromic") may be seen with conditions such as iron deficiency anemia or thalassemia, and MedlinePlus notes it is often linked to low iron levels. These are general possible associations, not a complete list, and a low value does not by itself confirm any specific condition. Note too that anemia can occur even when the red blood cell indices look normal — MedlinePlus notes that normal indices can be seen alongside anemia from causes such as sudden blood loss, long-term (chronic) disease, kidney failure, aplastic anemia, or an artificial heart valve — which is one reason results are always read together with other tests.
Reference ranges vary by laboratory, age, sex, and method — the range on your own report is what applies to you. A single value out of range doesn’t confirm any condition; your clinician interprets it alongside your symptoms, history, and other results. This page is general information, not medical advice.
General reference, not medical advice, and not a substitute for your clinician. Lab reference ranges and interpretation depend on the laboratory and on your individual situation — discuss your results with a licensed healthcare professional.