Neutrophil-Lymphocyte Ratio (NLR) Calculator

Neutrophil–Lymphocyte Ratio (NLR): Explanation and Clinical Context The Neutrophil–Lymphocyte Ratio (NLR) is calculated by dividing the absolute neutrophil count by the absolute lymphocyte count. It is an inexpensive and widely available marker of systemic inflammation. Elevated NLR has been associated with adverse outcomes in cardiovascular diseases, cancer, and critical illness.

Cut-offs vary by clinical context, but in cardiovascular risk stratification: <2 is considered low risk, 2–5 moderate risk, and >5 high risk of adverse outcomes. This ratio helps clinicians quickly assess the balance between innate (neutrophils) and adaptive (lymphocytes) immunity, reflecting systemic stress and inflammation.