What this calculator does
A full blood count reports how much haemoglobin is present and how many red cells carry it. MCH divides one by the other to give the average content per cell, while MCHC compares haemoglobin against packed cell volume to give concentration.
The two answer different questions. A haemoglobin of 10 g/dL gives an MCH of 20.0 pg and an MCHC of 22.2 g/dL, both below their reference ranges, but the first says cells contain less haemoglobin and the second says they are less densely packed with it.
The formula
MCH is haemoglobin divided by red cell count, scaled by 10. MCHC is haemoglobin divided by haematocrit, scaled by 100. Both come from values already on a standard count.
| Term | Meaning |
|---|---|
| MCH | Mean corpuscular haemoglobin: average mass of haemoglobin per red cell, in picograms. |
| MCHC | Mean corpuscular haemoglobin concentration: haemoglobin per unit of packed cell volume. |
| Hypochromic | Cells containing less haemoglobin than normal, which both indices can indicate. |
The inputs explained
| Field | What to enter |
|---|---|
| Haemoglobin (g/dL) | Haemoglobin in g/dL. |
| Red blood cell count (million/µL) | Red blood cell count in millions per microlitre. |
| Haematocrit (%) | Haematocrit as a percentage, the share of blood volume made up of red cells. |
When to use it
Classifying an anemia
The red cell indices are how an anemia is first categorised.
Reading a blood count
The indices are calculated from values already reported, so they cost nothing to check.
Spotting a laboratory error
An impossibly high MCHC usually indicates a sample problem rather than a real finding.
Worked examples
Every figure in the tables below is produced by this page’s own calculator at build time, so the numbers and the tool always agree. Select any row to load that scenario.
How does haemoglobin move both indices?
The same cell count and haematocrit at three haemoglobin levels.
Questions
What is the difference between MCH and MCHC?
MCH is the amount of haemoglobin per cell and MCHC is its concentration within the cell volume. A large cell can have a high MCH with a normal MCHC, because there is more haemoglobin spread through more volume.
Why is a very high MCHC suspicious?
Because red cells cannot hold haemoglobin beyond a physical limit of roughly 37 g/dL. Values above that usually indicate a measurement problem such as lipaemia, cold agglutinins or a clotted sample, rather than a real finding.
How do these relate to MCV?
MCV describes cell size, MCH and MCHC describe haemoglobin content and concentration. Together the three classify an anemia as microcytic, normocytic or macrocytic and as hypochromic or normochromic.
Can I interpret these myself?
They are best read alongside the whole count and the clinical picture. Abnormal indices have many causes and belong with the clinician who ordered the test.
For screening the same count for anemia type, see the Mentzer index calculator. For iron status, see the transferrin saturation calculator.