About

Medical laboratory reports often arrive as dense columns of numbers and abbreviations. For patients without a medical background, deciphering these values creates unnecessary anxiety. This tool acts as a preliminary interpreter for a Complete Blood Count (CBC). It compares input data against established hematological reference ranges derived from major health organizations.

A CBC evaluates three major components of blood: red blood cells (oxygen carriers), white blood cells (immune defense), and platelets (clotting agents). Deviations from the reference interval, often denoted as Ref, do not always indicate pathology. Factors such as hydration status, altitude, and recent physical activity influence these metrics. This decoder provides context by categorizing results into Low, Normal, or High ranges based on biological sex and age group constraints.

Formulas

While a CBC is a direct measurement, several indices are calculated relationships between the physical properties of red blood cells. Understanding these derivations helps in identifying specific types of anemia.

Mean Corpuscular Volume (MCV): Represents the average size of a red blood cell.

Hct × 10RBC

Mean Corpuscular Hemoglobin (MCH): Represents the average mass of hemoglobin per red blood cell.

Hgb × 10RBC

Mean Corpuscular Hemoglobin Concentration (MCHC):

Hgb × 100Hct

In these calculations, Hgb is measured in g/dL, Hct in %, and RBC in 10⁶/µL.

Reference Data

Parameter	Unit	Men (Adult)	Women (Adult)	Children (2-12y)
Hemoglobin (Hgb)	g/dL	13.5 − 17.5	12.0 − 15.5	11.5 − 15.5
Hematocrit (Hct)	%	38.8 − 50.0	34.9 − 44.5	35.0 − 45.0
Red Blood Cells (RBC)	10⁶/µL	4.32 − 5.72	3.90 − 5.03	4.00 − 5.20
White Blood Cells (WBC)	10³/µL	3.5 − 10.5	3.5 − 10.5	5.0 − 14.5
Platelets (Plt)	10³/µL	150 − 450	150 − 450	150 − 450
MCV (Mean Corpuscular Vol)	fL	80 − 100	80 − 100	77 − 95
MCH (Mean Corpuscular Hgb)	pg	27 − 33	27 − 33	25 − 33
Neutrophils	%	40 − 60	40 − 60	30 − 50
Lymphocytes	%	20 − 40	20 − 40	35 − 60

Frequently Asked Questions

Reference ranges are statistical definitions covering 95% of the healthy population. By definition, 5% of healthy individuals fall outside these limits. Minor deviations can occur due to dehydration, stress, recent meals, or medication. A single value slightly out of range is rarely a cause for immediate alarm without clinical context.

Generally, a Complete Blood Count does not require fasting. However, if the blood draw includes a lipid panel or glucose test, fasting is required. High fat content in blood (lipemia) can occasionally interfere with Hemoglobin measurements.

The differential count is often reported in percentages (relative). This tells you the proportion of one cell type relative to others. The absolute count (calculated as Total WBC × Percentage) is the actual number of cells per volume of blood. The absolute count is clinically more significant for diagnosing infections or immune deficiencies.

Pregnancy typically causes a physiological increase in plasma volume, leading to a lower Hemoglobin concentration (dilutional anemia) and a slight elevation in White Blood Cells. Smokers often have higher Hemoglobin and Hematocrit levels because carbon monoxide binds to red blood cells, forcing the body to produce more cells to maintain oxygen delivery.